Hidden Direct Bandgap of Bi2O2Se by Se Vacancy and Enhanced Direct Bandgap of Bismuth Oxide Overlayer

The Bi2O2Se surfaces are well-known to possess 50% Se vacancies, yet they have shown no in-gap states within the indirect bandgap (∼0.8 eV). We have found that the hidden in-gap states arising from the Se vacancies in a 2 × 1 pattern induce a reduced direct bandgap (∼0.5 eV). Such a reduced direct bandgap is responsible for the high electron mobility of Bi2O2Se. Moreover, the Bi oxide overlayers of the Bi thin films, formed through air exposure and annealing, unexpectedly exhibit a large direct bandgap (∼2.1 eV). The simplified fabrication of Bi oxide overlayers provides promise for improving Bi2O2Se electronic devices and enhancing photocatalytic activity.

Image Generation and Recognition for Railway Surface Defect Detection

Railway defects can result in substantial economic and human losses. Among all defects, surface defects are the most common and prominent type, and various optical-based non-destructive testing (NDT) methods have been employed to detect them. In NDT, reliable and accurate interpretation of test data is vital for effective defect detection. Among the many sources of errors, human errors are the most unpredictable and frequent. Artificial intelligence (AI) has the potential to address this challenge; however, the lack of sufficient railway images with diverse types of defects is the major obstacle to training the AI models through supervised learning. To overcome this obstacle, this research proposes the RailGAN model, which enhances the basic CycleGAN model by introducing a pre-sampling stage for railway tracks. Two pre-sampling techniques are tested for the RailGAN model: image-filtration, and U-Net. By applying both techniques to 20 real-time railway images, it is demonstrated that U-Net produces more consistent results in image segmentation across all images and is less affected by the pixel intensity values of the railway track. Comparison of the RailGAN model with U-Net and the original CycleGAN model on real-time railway images reveals that the original CycleGAN model generates defects in the irrelevant background, while the RailGAN model produces synthetic defect patterns exclusively on the railway surface. The artificial images generated by the RailGAN model closely resemble real cracks on railway tracks and are suitable for training neural-network-based defect identification algorithms. The effectiveness of the RailGAN model can be evaluated by training a defect identification algorithm with the generated dataset and applying it to real defect images. The proposed RailGAN model has the potential to improve the accuracy of NDT for railway defects, which can ultimately lead to increased safety and reduced economic losses. The method is currently performed offline, but further study is planned to achieve real-time defect detection in the future.

Thermoelectric performance of novel single-layer ZrTeSe4

Single-layer ZrTeSe4 is a novel 2D semiconductor as well as a promising candidate for 2D thermoelectric materials.

Postpartum haemorrhage requiring transfusion and risk of cardiovascular disease later in life: a retrospective cohort study

OBJECTIVE

To determine whether postpartum haemorrhage (PPH) is associated with cardiovascular disease (CVD), including cerebrovascular and ischaemic heart disease beyond the peripartum period.

DESIGN

Population-based cohort study.

SETTING

Merged databases of the Korea National Health Insurance (KNHI) claims, National Health Screening Examination and National Health Screening Program for Infants and Children.

POPULATION

Women who gave birth in 2007 in the Republic of Korea and who were tracked through to 2015 for the occurrence of CVD.

METHODS

Patients were identified and the occurrences of PPH and transfusion were determined using the KNHI claims database. The occurrence of CVD was tracked through 2015 using codes from the International Classification of Diseases, tenth revision (ICD-10).

MAIN OUTCOME MEASURES

The risk of CVD after PPH.

RESULTS

Among 150 381 women who gave birth during the study period, 9107 were diagnosed with PPH and 899 were treated with transfusion. The risk of CVD in women with PPH was no different than in women without PPH, after adjustment (HR 1.03, 95% CI 0.93-1.13). The risk of CVD in women with PPH requiring transfusion was significantly increased compared with women without PPH, after adjustment (HR 1.60, 95% CI 1.25-2.06). The risk of CVD in women with PPH without transfusion was not significantly different compared with women without PPH (HR 0.96, 95% CI 0.86-1.07).

CONCLUSIONS

Postpartum haemorrhage (PPH) requiring transfusion is associated with an increased risk of CVD. Guidelines for management should be established, and further studies on the mechanisms involved should be conducted.

TWEETABLE ABSTRACT

PPH requiring transfusion is associated with an increased risk of CVD.

Association between body mass index and stroke severity in acute ischaemic stroke with non-valvular atrial fibrillation

BACKGROUND AND PURPOSE

The objective of this study was to investigate the association between body mass index (BMI) and both initial stroke severity at presentation and functional outcomes after acute ischaemic stroke (AIS) in patients with non-valvular atrial fibrillation (NVAF).

METHODS

Patients were categorized on the basis of their BMI into underweight (BMI <18.5, n = 111), normal (18.5 ≤ BMI <25, n = 1036) and overweight to obese (BMI ≥25, n = 472) groups. Initial stroke severity was assessed using the National Institutes of Health Stroke Scale (NIHSS) score and functional outcomes were assessed using the modified Rankin Scale score at discharge. The differences in stroke severity and functional outcomes were compared between groups using robust log-linear regression with a Poisson distribution and binary logistic regression analysis.

RESULTS

A total of 1619 AIS patients with NVAF from six hospitals were included. Compared with the NIHSS scores [median 5, interquartile range (IQR) 2-14] of normal-weight patients, the NIHSS scores (median 9, IQR 4-19) of underweight patients were more likely to be higher, whereas those of overweight to obese patients were lower (median 4, IQR 1-12) (P < 0.001). In terms of functional outcomes after stroke, underweight patients had a higher risk of poor functional outcomes (odds ratio 1.78, 95% confidence interval 1.09-2.56, P = 0.01) but overweight to obese patients had no significant difference in functional outcomes compared with normal-weight patients.

CONCLUSION

An inverse association was found between BMI and stroke severity in AIS patients with NVAF. This suggests the presence of an obesity paradox for short-term outcomes in patients with NVAF.

Thermally driven homonuclear-stacking phase of MoS2 through desulfurization

Engineering phase transitions or finding new polymorphs offers tremendous opportunities for developing functional materials. We reveal that the thermally driven desulfurization of single-crystalline MoS2 samples improves transport properties by reducing the band gap and further induces metallization. Semi-desulfurization, i.e., removal of the topmost S layer, results in the placement of the exposed Mo layers directly on top of the following sub-layers, together with the bottom S layer of the top layer. This homonuclear (AA) stacking derived from the AA' stacking of the hexagonal (2H) phase is retained even after further desulfurization of the remaining bottom S layer, i.e., full desulfurization of the top layer. Our findings fundamentally explain why the 2H phase of TMDs is characterized by AA' stacking.

Adsorption and Oxidative Desorption of Acetaldehyde over Mesoporous Fe x O y H z /Al2O3

Fe _x O _y H _z nanostructures were incorporated into commercially available and highly porous alumina using the temperature-regulated chemical vapor deposition method with ferrocene as an Fe precursor and subsequent annealing. All processes were conducted under ambient pressure conditions without using any high-vacuum equipment. The entire internal micro- and mesopores of the Al₂O₃ substrate with a bead diameter of ∼2 mm were evenly decorated with Fe _x O _y H _z nanoparticles. The Fe _x O _y H _z /Al₂O₃ structures showed substantially high activity for acetaldehyde oxidation. Most importantly, Fe _x O _y H _z /Al₂O₃ with a high surface area (∼200 m²/g) and abundant mesopores was found to uptake a large amount of acetaldehyde at room temperature, and subsequent thermal regeneration of Fe _x O _y H _z /Al₂O₃ in air resulted in the emission of CO₂ with only a negligibly small amount of acetaldehyde because Fe _x O _y H _z nanoparticles can catalyze total oxidation of adsorbed acetaldehyde during the thermal treatment. Increase in the humidity of the atmosphere decreased the amount of acetaldehyde adsorbed on the surface due to the competitive adsorption of acetaldehyde and water molecules, although the adsorptive removal of acetaldehyde and total oxidative regeneration were verified under a broad range of humidity conditions (0-70%). Combinatory use of room-temperature adsorption and catalytic oxidation of adsorbed volatile organic compounds using Fe _x O _y H _z /Al₂O₃ can be of potential application in indoor and outdoor pollution treatments.

Core-Shell Structured Cobalt Sulfide/Cobalt Aluminum Hydroxide Nanosheet Arrays for Pseudocapacitor Application

The direct synthesis of nanostructured electrode materials on three-dimensional substrates is important for their practical application in electrochemical cells without requiring the use of organic additives or binders. In this study, we present a simple two-step process to synthesize a stable core-shell structured cobalt sulfide/cobalt aluminum hydroxide nanosheet (LDH-S) for pseudocapacitor electrode application. The cobalt aluminum layered double hydroxide (CoAl-LDH) nanoplates were synthesized in basic aqueous solution with a kinetically-controlled thickness. Owing to the facile diffusion of electrolytes through the nanoplates, thin CoAl-LDH nanoplates have higher specific capacitance values than thick nanoplates. The as-grown CoAl-LDH nanoplates were transformed into core-shell structured LDH-S nanosheets by a surface modification process in Na₂ S aqueous solution. The chemically robust cobalt sulfide (CoS) shell increased the electrochemical stability compared to the sulfide-free CoAl-LDH electrodes. The LDH-S electrodes exhibited high electrochemical performance in terms of specific capacitance and rate capability with a galvanostatic discharge of 1503 F g^-1 at a current density of 2 A g^-1 and a specific capacitance of 91 % at 50 A g^-1 .

Hydrogen interaction with a sulfur-vacancy-induced occupied defect state in the electronic band structure of MoS2

A combination study of photoemission spectroscopy and first-principles calculations reveals that a sufficiently high concentration (2.8–11.1%) of the V_S defect on the MoS₂ surface induces an occupied defect state in the electronic band structure, in addition to the in-gap defect states.

Highly intense room-temperature photoluminescence in V2O5 nanospheres

Room-temperature photoluminescence (PL) in V₂O₅ nanospheres with zero-like dimensional structure was investigated. A large number of V⁴⁺ oxidation states in the nanospheres were observed by X-ray photoelectron spectroscopy (XPS) measurements. The nanospheres revealed high PL intensity compared with previous studies. In particular, they showed intense ultraviolet (UV) PL near a wavelength of 396 nm (3.13 eV). The intense UV PL was attributed to the enhanced transition probability due to the large number of V⁴⁺ (3d¹) oxidation states. The PL properties showed strong dependencies on the oxidation states and their distribution.

Room-temperature photoluminescence (PL) in V₂O₅ nanospheres with zero-like dimensional structure was investigated.

Interplay between many body effects and Coulomb screening in the optical bandgap of atomically thin MoS2

Due to its unique layer-number dependent electronic band structure and strong excitonic features, atomically thin MoS₂ is an ideal 2D system where intriguing photoexcited-carrier-induced phenomena can be detected in excitonic luminescence. We perform micro-photoluminescence (PL) measurements and observe that the PL peak redshifts nonlinearly in mono- and bi-layer MoS₂ as the excitation power is increased. The excited carrier-induced optical bandgap shrinkage is found to be proportional to n^4/3, where n is the optically-induced free carrier density. The large exponent value of 4/3 is explicitly distinguished from a typical value of 1/3 in various semiconductor quantum well systems. The peculiar n^4/3 dependent optical bandgap redshift may be due to the interplay between bandgap renormalization and reduced exciton binding energy.

Molecular functions of Xanthomonas type III effector AvrBsT and its plant interactors in cell death and defense signaling

Xanthomonas effector AvrBsT interacts with plant defense proteins and triggers cell death and defense response. This review highlights our current understanding of the molecular functions of AvrBsT and its host interactor proteins. The AvrBsT protein is a member of a growing family of effector proteins in both plant and animal pathogens. Xanthomonas type III effector AvrBsT, a member of the YopJ/AvrRxv family, suppresses plant defense responses in susceptible hosts, but triggers cell death signaling leading to hypersensitive response (HR) and defense responses in resistant plants. AvrBsT interacts with host defense-related proteins to trigger the HR cell death and defense responses in plants. Here, we review and discuss recent progress in understanding the molecular functions of AvrBsT and its host interactor proteins in pepper (Capsicum annuum). Pepper arginine decarboxylase1 (CaADC1), pepper aldehyde dehydrogenase1 (CaALDH1), pepper heat shock protein 70a (CaHSP70a), pepper suppressor of the G2 allele of skp1 (CaSGT1), pepper SNF1-related kinase1 (SnRK1), and Arabidopsis acetylated interacting protein1 (ACIP1) have been identified as AvrBsT interactors in pepper and Arabidopsis. Gene expression profiling, virus-induced gene silencing, and transient transgenic overexpression approaches have advanced the functional characterization of AvrBsT-interacting proteins in plants. AvrBsT is localized in the cytoplasm and forms protein-protein complexes with host interactors. All identified AvrBsT interactors regulate HR cell death and defense responses in plants. Notably, CaSGT1 physically binds to both AvrBsT and pepper receptor-like cytoplasmic kinase1 (CaPIK1) in the cytoplasm. During infection with Xanthomonas campestris pv. vesicatoria strain Ds1 (avrBsT), AvrBsT is phosphorylated by CaPIK1 and forms the active AvrBsT-CaSGT1-CaPIK1 complex, which ultimately triggers HR cell death and defense responses. Collectively, the AvrBsT interactor proteins are involved in plant cell death and immunity signaling.

Low Temperature CO oxidation over Iron Oxide Nanoparticles Decorating Internal Structures of a Mesoporous Alumina

Using a chemical vapor deposition method with regulated sample temperatures under ambient pressure conditions, we were able to fully decorate the internal structure of a mesoporous Al₂O₃ bead (~1 mm in particle diameter) with iron oxide nanoparticles (with a mean lateral size of less than 1 nm). The iron oxide-decorated Al₂O₃ showed a high CO oxidation reactivity, even at room temperature. Very little deactivation of the CO oxidation activity was observed with increasing reaction time at ~100 °C. Additionally, this catalyst showed high CO oxidation activity, even after annealing at ~900 °C under atmospheric conditions (i.e., the structure of the catalysts could be maintained under very harsh treatment conditions). We show that our catalysts have potential for application as oxidation catalysts in industrial processes due to the simplicity of their fabrication process as well as the high and stable catalytic performance.

Impact of caudal block on postoperative complications in children undergoing tubularised incised plate urethroplasty for hypospadias repair: a retrospective cohort study

This study aimed to assess the association between caudal block and postoperative complications after tubularised incised plate urethroplasty. The medical records of 388 paediatric patients who underwent urethroplasty at a tertiary medical centre were analysed retrospectively. Among the 342 patients included, 216 patients received a caudal block and 72 (21.1%) patients suffered surgical complications. The number of patients having surgical complications was significantly greater among patients who received a caudal block than among patients who did not receive a caudal block (53 (24.5%) versus 19 (15.1%), respectively, p = 0.04). Based on multivariate logistic regression analysis, duration of surgery, caudal block and hypospadias types were independent risk factors for the surgical complications. Patients with caudal block had an odds ratio of 2.1 (95% CI, 1.14-3.81, p = 0.018) for the development of postoperative complications compared with patients without caudal block. This analysis demonstrates that caudal block is associated with surgical complications after tubularised incised plate urethroplasty.

Abstract A28: NFATC3-PLA2G15 fusion transcript identified by RNA-sequencing promotes tumor progression in colorectal cancer cells

In order to identify novel fusion transcripts in colorectal cancer, we carried out paired-end RNA sequencing in 28 human colorectal cancer cell lines. Fusion transcript candidates were identified using ChimeraScan and FusionMap tools. We obtained 1380 candidates having 4 or more read counts and spanning reads. Among the candidates, we selected 27 candidates for validation which harbors genes related to the Wnt signaling pathway or kinases according to KEGG or DAVID. After the targeted gene filtering step, validation using RT-PCR with fusion specific primers finally resulted in 2 intra- and 1 inter-fusion transcripts. Intra-fusion transcripts were NFATC3-PLA2G15 and AKAP13-PDE8A and inter-fusion transcript was KRT8-PKM2 each identified in colo-320, SW-480 and SNU-1235, respectively. The fusion junctions were confirmed by Sanger sequencing. NFATC3-PLA2G15 fusion transcripts consisted of exon 1-9 of NFATC3 (nuclear factor of activated T-cells, cytoplasmic 3) gene and exon 2-6 of the PLA2G15 (Phospholipase A2, Group 5) gene and both located on the same chromosome 16q. NFATC3 is known as transcription factor in the Wnt signaling pathway and regulates function of the target genes like cell proliferation, invasion and epithelial-to-mesenchymal transition (EMT). Under the experiments using siRNA in the colo-320 cell carrying fusion transcript, knockdown of the NFATC3-PLA2G15 fusion transcript decreased mRNA and protein expression of mesenchymal markers, namely vimentin (VIM), Twist-related protein 1 (TWIST1) and fibronectin (FN), and increased epithelial markers, E-cadherin (CDH1) and claudin-1 (CLDN1). Fusion transcripts knockdown also led to decrease of the invasion ability regulated by above markers. Moreover, soft agar assay showed inhibition of colony formation after fusion transcript knockdown. Fusion transcript downregulation also resulted in decrease of cell proliferation and mRNA and protein expression of cyclin D but increase in p27 level. The knockdown did not have influence in the fusion negative cell line. Collectively, these results suggest that the NFATC3-PLA2G15 fusion transcript is involved in invasion and proliferation of colorectal cancer cells.

Citation Format: JE Jang, HP Kim, SH Lee, DW Lee, YJ Lim, SW Han, TY Kim. NFATC3-PLA2G15 fusion transcript identified by RNA-sequencing promotes tumor progression in colorectal cancer cells. [abstract]. In: Proceedings of the AACR-NCI-EORTC International Conference: Molecular Targets and Cancer Therapeutics; 2015 Nov 5-9; Boston, MA. Philadelphia (PA): AACR; Mol Cancer Ther 2015;14(12 Suppl 2):Abstract nr A28.

Disruption of CTCF/cohesin-mediated high-order chromatin structures by DNA methylation downregulates PTGS2 expression

The CCCTC-binding factor (CTCF)/cohesin complex regulates gene transcription via high-order chromatin organization of the genome. De novo methylation of CpG islands in the promoter region is an epigenetic hallmark of gene silencing in cancer. Although the CTCF/cohesin complex preferentially targets hypomethylated DNA, it remains unclear whether the CTCF/cohesin-mediated high-order chromatin structure is affected by DNA methylation during tumorigenesis. We found that DNA methylation downregulates the expression of prostaglandin-endoperoxide synthase 2 (PTGS2), which is an inducible, rate-limiting enzyme for prostaglandin synthesis, by disrupting CTCF/cohesin-mediated chromatin looping. We show that the CTCF/cohesin complex is enriched near a CpG island associated with PTGS2 and that the PTGS2 locus forms chromatin loops through methylation-sensitive binding of the CTCF/cohesin complex. DNA methylation abolishes the association of the CTCF/cohesin complex with the PTGS2 CpG island. Disruption of chromatin looping by DNA methylation abrogates the enrichment of transcriptional components, such as positive elongation factor b, at the transcriptional start site of the PTGS2 locus. These alterations result in the downregulation of PTGS2. Our results provide evidence that CTCF/cohesin-mediated chromatin looping of the PTGS2 locus is dynamically influenced by the DNA methylation status.

Infection processes of xylem-colonizing pathogenic bacteria: possible explanations for the scarcity of qualitative disease resistance genes against them in crops

Disease resistance against xylem-colonizing pathogenic bacteria in crops. Plant pathogenic bacteria cause destructive diseases in many commercially important crops. Among these bacteria, eight pathogens, Ralstonia solanacearum, Xanthomonas oryzae pv. oryzae, X. campestris pv. campestris, Erwinia amylovora, Pantoea stewartii subsp. stewartii, Clavibacter michiganensis subsp. michiganensis, Pseudomonas syringae pv. actinidiae, and Xylella fastidiosa, infect their host plants through different infection sites and paths and eventually colonize the xylem tissues of their host plants, resulting in wilting symptoms by blocking water flow or necrosis of xylem tissues. Noticeably, only a relatively small number of resistant cultivars in major crops against these vascular bacterial pathogens except X. oryzae pv. oryzae have been found or generated so far, although these pathogens threaten productivity of major crops. In this review, we summarize the lifestyles of major xylem-colonizing bacterial pathogens and then discuss the progress of current research on disease resistance controlled by qualitative disease resistance genes or quantitative trait loci against them. Finally, we propose infection processes of xylem-colonizing bacterial pathogens as one of possible reasons for why so few qualitative disease resistance genes against these pathogens have been developed or identified so far in crops.

Micro-Structural Properties of YBa2Cu3O(7-x)/ZnO Nanorods on SrTiO3

We examined the local structural and the interfacial properties of YBa2Cu3O(7-x) (YBCO)/ZnO nanorods on SrTiO3 (STO) substrates using various measurements. Vertically aligned ZnO nanorods were synthesized on STO substrates using a catalyst-free metal-organic chemical vapor deposition. YBCO films were deposited ex-situ on the ZnO nanorods/STO templates using a DC magnetron sputtering deposition. X-ray diffraction revealed that the YBCO films were crystallized along their c-axes on the ZnO nanorods/STO templates. Transmission electron microscopy measurements demonstrated that YBCO filled the space between ZnO nanorods and that both interfaces of YBCO/ZnO nanorods and ZnO nanorods/STO were quite clean with no disorder. Polarization-dependent extended X-ray absorption fine structure measurements at the Cu K edge showed extra disorder in the CuO2 planes of YBCO/ZnO nanorods/STO, compared with that of YBCO/STO. The superconductivity transition temperature (T(c)) of YBCO/ZnO nanorods/STO was approximately 50 K whereas that of YBCO/STO was 93 K. The decrease of T(c) of YBCO/ZnO nanorods/STO was ascribed to the structural disorder of CuO2 planes as well as grain boundaries in the YBCO films.

Fabrication of superhydrophobic thin films on various substrates using SiO2 nanoparticles coated with polydimethylsiloxane: towards the development of shielding layers for gas sensors

Superhydrophobic membranes with high gas permeability were prepared and characterized.

Apparent treatment-resistant hypertension among elderly Korean hypertensives: an insight from the HIT registry

The aim of this study was to determine the clinical characteristics of patients with resistant hypertension (RH) and predictors among elderly Korean hypertensives. This prospective, multi-center, observational study evaluated 2439 elderly hypertensive patients between December 2008 and November 2011, who visited secondary hypertension clinics for high blood pressure (BP). Patients were categorized as resistant if their BP was ≥140/90 mm Hg and if they reported using antihypertensive medications from three different drug classes, including a diuretic or drugs from ≥4 antihypertensive drug classes, regardless of BP. Characteristics of patients with RH were compared with those of patients who were controlled with one or two antihypertensive medications after 6-month antihypertensive treatment. In comparison with 837 patients with non-RH, 404 patients with RH were more likely to be aware of their status of high BP before enrollment and have a high baseline systolic BP ≥160 mm Hg, microalbuminuria, high body mass index (BMI) ≥24 kg m(-2) and diabetes mellitus (DM). In drug-naive patients, awareness of hypertension at baseline was the only independent predictor for RH. In elderly Korean hypertensives, BMI (≥24 kg m(-2)), baseline systolic BP (≥160 mm Hg), microalbuminuria, DM and awareness of hypertension showed an association with RH.

Controlling ferromagnetic easy axis in a layered MoS2 single crystal

We report the effective methods to induce weak ferromagnetism in pristine MoS2 persisting up to room temperature with the improved transport property, which would lead to new spintronics devices. The hydrogenation of MoS2 by heating at 300 °C for 1 h leads to the easy axis out of plane, while the irradiation of proton with a dose of 1 × 10(13) P/cm(2) leads to the easy axis in plane. The theoretical modeling supports such magnetic easy axes.

Orientation-dependent local structural properties of Zn(1-x)Mg(x)O nanorods studied by extended X-ray absorption fine structure

The orientation-dependent structural properties of Zn(1-x)Mg(x)O nanorods with different Mg concentrations were investigated quantitatively using polarization-dependent extended X-ray absorption fine structure (EXAFS) measurements at the Zn K edge. Vertically-aligned Zn(1-x)Mg(x)O nanorods were synthesized on Si substrates using catalyst free metal organic chemical vapor deposition. Polarization-dependent EXAFS measurements showed that Mg ions mainly occupied the Zn sites of the nanorods. EXAFS revealed that the distance between Zn-Mg pairs in all directions is - 0.2 angstroms shorter than that of Zn-Zn pairs and that there is a substantial amount of disorder in the Mg sites of the nanorods, independent of Mg concentrations.

Abstract PD09-05: Single nucleotide polymorphism of XRCC1 which participates in DNA repair mechanism predicts clinical outcome in relapsed or metastatic breast cancer patients treated with S1 and oxaliplatin chemotherapy: Results from multicenter prospective study (TORCH_KCSG BR07-03)

Background: S1 and oxaliplatin (SOX) combination chemotherapy is an effective regimen in anthracycline and taxane pretreated metastatic breast cancer (MBC) patients with manageable toxicities (KCSG BR07-03, SABCS 2011 #Abst P3-16-06). The aim of this study was to investigate the association of the single nucleotide polymorphisms (SNPs) and clinical outcome in MBC treated with SOX chemotherapy.

Patients and Methods: A total of 87 MBC patients previously treated with or resistant to anthracycline and taxane chemotherapy were enrolled in this prospective multicenter trial. The patients received S-1 80mg/m2/day (day 1–14) and oxaliplatin 130 mg/m2 (day 1) every 3 weeks till progression. Among the 87 patients, 77 patients were available for SNP analysis. Germline DNA from peripheral blood (PB) mononuclear cells was extracted. SNPs in 4 genes from pathways that may influence cellular sensitivity to S1 and oxaliplatin (TS, ERCC, XPD, and XRCC) were genotyped from PB sample using PCR-restriction fragment length polymorphism.

Results: Overall response rate (RR) was 38.5% (95% CI: 27.7–49.3) and disease control rate was 67.9% (95% CI:57.5–78.3) to SOX. Median time-to-progression (TTP) and overall survival (OS) were 6.0 mo (95% CI: 5.1–6.9 mo) and 19.4 mo (95% CI: not estimated), respectively. XRCC1 Arg194Trp SNP which participates in DNA repair mechanism showed correlation with the clinical outcome. RR was tend to higher in XRCC1 Arg194Trp CC genotype compared with CT or TT genotype (50.0 % vs 35.1% or 12.5%, P = 0.121). TTP of patients with CC genotype in XRCC1 Arg194Trp was significantly longer than the TTP of patients with CT or TT genotype (median TTP: 6.4 mo in CC, 5.9 mo in CT, 3.0 mo in TT, P = 0.007) as well as overall survival (OS) (median OS: not reached in CC, 13.9 mo in CT, 7.1 mo in TT, P = 0.006). After adjusting for hormone receptor status, performance status, and visceral involvement, prognostic value of XRCC1 Arg194Trp SNP remained significant (Hazard Ratio=1.322 and 4.484, P = 0.016). Other SNPs were not significantly associated with survival or toxicities.

Conclusion: XRCC1 Arg194Trp SNP is associated with clinical outcome of MBC patients treated with SOX chemotherapy. Further studies of the relationship between germline polymorphisms in XRCC1 and functional mechanism researches are warranted.

Citation Information: Cancer Res 2012;72(24 Suppl):Abstract nr PD09-05.

Double gene therapy with granulocyte colony-stimulating factor and vascular endothelial growth factor acts synergistically to improve nerve regeneration and functional outcome after sciatic nerve injury in mice

Peripheral-nerve injuries are a common clinical problem and often result in long-term functional deficits. Reconstruction of peripheral-nerve defects is currently undertaken with nerve autografts. However, there is a limited availability of nerves that can be sacrificed and the functional recovery is never 100% satisfactory. We have previously shown that gene therapy with vascular endothelial growth factor (VEGF) significantly improved nerve regeneration, neuronal survival, and muscle activity. Our hypothesis is that granulocyte colony-stimulating factor (G-CSF) synergizes with VEGF to improve the functional outcome after sciatic nerve transection. The left sciatic nerves and the adjacent muscle groups of adult mice were exposed, and 50 or 100 μg (in 50 μl PBS) of VEGF and/or G-CSF genes was injected locally, just below the sciatic nerve, and transferred by electroporation. The sciatic nerves were transected and placed in an empty polycaprolactone (PCL) nerve guide, leaving a 3-mm gap to challenge nerve regeneration. After 6 weeks, the mice were perfused and the sciatic nerve, the dorsal root ganglion (DRG), the spinal cord and the gastrocnemius muscle were processed for light and transmission electron microscopy. Treated animals showed significant improvement in functional and histological analyses compared with the control group. However, the best results were obtained with the G-CSF+VEGF-treated animals: quantitative analysis of regenerated nerves showed a significant increase in the number of myelinated fibers and blood vessels, and the number of neurons in the DRG and motoneurons in the spinal cord was significantly higher. Motor function also showed that functional recovery occurred earlier in animals receiving G-CSF+VEGF-treatment. The gastrocnemius muscle showed an increase in weight and in the levels of creatine phosphokinase, suggesting an improvement of reinnervation and muscle activity. These results suggest that these two factors acted synergistically and optimized the nerve repair potential, improving regeneration after a transection lesion.

CCR5 gene polymorphism is a genetic risk factor for radiographic severity of rheumatoid arthritis

The chemokine receptor [C-C chemokine receptor 5 (CCR5)] is expressed on diverse immune effecter cells and has been implicated in the pathogenesis of rheumatoid arthritis (RA). This study sought to determine whether single-nucleotide polymorphisms (SNPs) in the CCR5 gene and their haplotypes were associated with susceptibility to and severity of RA. Three hundred fifty-seven patients with RA and 383 healthy unrelated controls were recruited. Using a pyrosequencing assay, we examined four polymorphisms -1118 CTAT(ins) (/del) (rs10577983), 303 A>G (rs1799987), 927 C>T (rs1800024), and 4838 G>T (rs1800874) of the CCR5 gene, which were distributed over the promoter region as well as the 5' and 3' untranslated regions. No significant difference in the genotype, allele, and haplotype frequencies of the four selected SNPs was observed between RA patients and controls. CCR5 polymorphisms of -1118 CTAT(del) (P = 0.012; corrected P = 0.048) and 303 A>G (P = 0.012; corrected P = 0.048) showed a significant association with radiographic severity in a recessive model, and, as a result of multivariate logistic regression analysis, were found to be an independent predictor of radiographic severity. When we separated the erosion score from the total Sharp score, the statistical significance of CCR5 polymorphisms showed an increase; -1118 CTAT(ins) (/del) (P = 0.007; corrected P = 0.028) and 303 A>G (P = 0.007; corrected P = 0.028). Neither SNPs nor haplotypes of the CCR5 gene showed a significant association with joint space narrowing score. These results indicate that genetic polymorphisms of CCR5 are an independent risk factor for radiographic severity denoted by modified Sharp score, particularly joint erosion in RA.

Preparation of MoO3/MoS2/TiO2 composites for catalytic degradation of methylene blue

Metastable hexagonal MoO3 microrods were grown from bulk MoS2 and used as support materials for MoS2 and TiO2 nanoparticles. The hybrid composites that consisted of MoO3, MoS2, and TiO2 were prepared at a low temperature using the one-step synthesis method. The crystallinity and morphology of the MoO3/MoS2/TiO2 composites that were prepared using HNO3 and titanium tetraisopropoxide were compared with those of the MoO3/MoS2 composites that were prepared without titanium tetraisopropoxide. Titanium isopropoxide facilitated the formation of the MoO3 microrods from the oxidation of the bulk MoS2. The desired MoO3/MoS2/TiO2 composites were obtained using 0.5 g of bulk MoS2, 3-4 ml of HNO3, and 0.367 ml of titanium tetraisopropoxide. The MoO3/MoS2/TiO2 composites that were treated with ultrasonic waves showed rapid degradation of the methylene blue solution (2 x 10(-4) M) in the dark and good photocatalytic ability under ultraviolet light irradiation. The decomposition of methylene blue depended on the composition of the composite.

P3-16-06: Phase II Trial of TS-1 in Combination with Oxaliplatin (SOX) in Patients with Metastatic Breast Cancer (MBC) Previously Treated with Anthracycline and Taxane Chemotherapy [TORCH] [Korean Cancer Study Group (KCSG) BR07-03]

Background

Oxaliplatin, a platinum analogue, is an active drug in advanced anthracycline and taxane-pretreated breast cancer patients as a single agent and with 5-fluorouracil (5-FU) combination. TS-1 was developed by the scientific theory of both potentiating antitumor activity of 5-FU and reducing gastrointestinal toxicity. This trial was performed to evaluate the efficacy and safety of TS-1 in combination with oxaliplatin in metastatic breast cancer (MBC) patients previously treated with anthracycline and taxane chemotherapy.

Methods: Between October 2007 and October 2009, MBC patients were enrolled in this prospective multicenter trial. Eligible criteria included age ≥18 years, at least one measurable lesion, prior treatment with anthracycline and taxane chemotherapy, and ECOG Performance Status 0–2. TS-1 40 mg/m2 b.i.d. on days 1–14 with oxaliplatin 130 mg/m2 on day 1 were administered every 3 weeks till disease progression. Primary end-point was response rate, and secondary end-points were time-to-progression (TTP), overall survival (OS), duration of response (DOR) and toxicities. Response was evaluated every 6 weeks according to the RECIST criteria v. 1.0 and toxicity was assessed with NCICTCAE v.3.0.(ClinicalTrials.gov identifier NCT00527930).

Results: A total of 87 patients were enrolled. Median age was 48 years (range 30–71 years). Nineteen patients (21.8%) had de novo stage IV and 68 patients (78.2%) had recurrent disease. Thirty-five patients (40.2%) received two-lines of prior chemotherapy in palliative setting. Forty-eight patients (55.2%) had ≥ 3 disease sites. Fifty-four patients (62.1%) were hormone receptor positive, and 25 patients (28.7%) were triple negative. Five patients received prior anti-HER2 therapy. A total of 525 cycles were administered (median 6 cycles, range: 1 ∼ 22+ cycle). In per-protocol analysis, overall response rate was 38.5% (95% CI: 27.7−49.3) (CR 0%, PR 38.5%) and disease control rate (CR, PR, and SD) was 67.9% (95% CI: 57.5−78.3). Median TTP, OS, and DOR were 6.0 months (95% CI: 5.1−6.9 months), 19.4 months (95% CI: not estimated), 6.6 months (95% CI: 3.7−9.6 months), respectively. RR was not different by triple negativity (39.1% in TNBC vs. 38.2% in non-TNBC, P=0.361). TTP was not different according to the number of prior chemotherapy regimens. Reported grade 3 or 4 toxicities (per cycle) were neutropenia (10.3%), thrombocytopenia (5.5%), diarrhea (1.9%), vomiting (1.9%), and stomatitis (0.2%). There was no treatment-related death.

Conclusions: SOX is an effective regimen in anthracycline and taxane pretreated MBC patients with manageable toxicities.

Citation Information: Cancer Res 2011;71(24 Suppl):Abstract nr P3-16-06.

Insular cortex is a trait marker for pain processing in fibromyalgia syndrome--blood oxygenation level-dependent functional magnetic resonance imaging study in Korea

OBJECTIVES

To investigate the variability in cerebral activation according to pain intensity and the association between variability in cerebral activation and clinical features in patients with fibromyalgia syndrome (FMS) using functional magnetic resonance imaging (fMRI).

METHODS

Nineteen FMS female patients and 22 age-matched healthy female controls were enrolled in this study. Changes in cerebral activation area were measured using blood oxygenation level-dependent (BOLD) contrast fMRI after application of both medium and high pressure stimuli to the left thumbnail bed.

RESULTS

We identified the insular cortex (IC) and superior temporal gyrus (STG) as regions of interest (ROIs) in this analysis. Cerebral activation at the bilateral IC in response to high pressure stimuli was significantly greater in FMS patients than it was in the controls, whereas there were no differences in BOLD signal changes in the STG regions between FMS patients and controls, irrespective of pain level. Prominent signal changes at both ROIs in FMS patients were noted between high and medium pressure (p<0.001 contralateral IC, p=0.001 for ipsilateral IC, p=0.008 for contralateral STG, and p=0.049 for ipsilateral STG). BOLD signal changes on the contralateral STG after medium stimuli were correlated with tender point count (r=0.586, p=0.013).

CONCLUSIONS

This study revealed more distinct signal variability in the ICs in FMS patients than in those of controls in response to high pressure stimuli. The IC can therefore be considered to be a region susceptible to pain perception in FMS patients.

Targeting apoptotic signaling pathways in human lung cancer

Lung carcinoma is the leading cause of carcinoma death in the world. Despite recent advances in understanding the molecular biology of lung cancer and the introduction of new therapeutic agents for its treatment, its dismal 5-year survival rate has not changed substantially. Clinical approaches have not significantly improved the survival of patients with advanced lung cancer. However, recent discoveries about the molecular mechanisms responsible for lung cancer initiation and proliferation have unveiled new targets for therapy. One of the hallmark features of cancer cells is their ability to evade programmed cell death or apoptosis. Alterations in pro- and anti-apoptotic pathways are common in cancer cells and defects in regulation of apoptosis have been implicated in both lung tumorigenesis and drug resistance. Thus, targeting apoptosis through the direct or indirect manipulation of the pro-apoptotic machinery offers a novel strategy for treatment. This mini review summaries the molecular events that contribute to drug-induced apoptosis and how lung tumors evade apoptotic death followed by an analysis of the implications for treatment.

Gene expression promoted by the SV40 DNA targeting sequence and the hypoxia-responsive element under normoxia and hypoxia

The main objective of the present study was to find suitable DNA-targeting sequences (DTS) for the construction of plasmid vectors to be used to treat ischemic diseases. The well-known Simian virus 40 nuclear DTS (SV40-DTS) and hypoxia-responsive element (HRE) sequences were used to construct plasmid vectors to express the human vascular endothelial growth factor gene (hVEGF). The rate of plasmid nuclear transport and consequent gene expression under normoxia (20% O2) and hypoxia (less than 5% O2) were determined. Plasmids containing the SV40-DTS or HRE sequences were constructed and used to transfect the A293T cell line (a human embryonic kidney cell line) in vitro and mouse skeletal muscle cells in vivo. Plasmid transport to the nucleus was monitored by real-time PCR, and the expression level of the hVEGF gene was measured by ELISA. The in vitro nuclear transport efficiency of the SV40-DTS plasmid was about 50% lower under hypoxia, while the HRE plasmid was about 50% higher under hypoxia. Quantitation of reporter gene expression in vitro and in vivo, under hypoxia and normoxia, confirmed that the SV40-DTS plasmid functioned better under normoxia, while the HRE plasmid was superior under hypoxia. These results indicate that the efficiency of gene expression by plasmids containing DNA binding sequences is affected by the concentration of oxygen in the medium.

Comment on "temperature-dependent localized excitations of doped carriers in superconducting diamond"

A Comment on the Letter by K. Ishizaka et al., Phys. Rev. Lett. 100, 166402 (2008)10.1103/PhysRevLett.100.166402. The authors of the Letter offer a Reply.

Quantum-well states in Cu/Fe/Cu(111) coupled to the bulk band through the barrier

The quantum-well state (QWS) has been observed on the surface of Cu/Fe/Cu(111). The confinement of the states on the top Cu layers is due to the minority spin barrier of the Fe underlayer. This QWS coexists with the Shockley surface state, which is observed on a clean Cu(111) surface. The resonant behavior of this QWS versus photon energy results from the vertical transition to the unoccupied bulk band, which is possibly due to the coupling between the overlayer Cu and the substrate Cu(111).

Sharp contrasts in low-energy quasiparticle dynamics of graphite between Brillouin zone K and H points

The low-energy quasiparticle (QP) dynamics of graphite are governed by a coupling with the E(2g) longitudinal optical phonon of omega(LO) approximately 200 meV, which is found to dramatically depend on the electronic band dispersion epsilon(k). A discontinuity of the QP linewidth develops near omega(LO) for a linear band with a quadratic band top [near the Brillouin zone (BZ) K point], while it disappears for a pure linear band (near the BZ H point). It is also found that the effective electron-phonon coupling near the K point is stronger than near the H point by more than 50%. This finding makes possible a consistent understanding of recent angle-resolved photoemission observations near the K point.

Successful endoscopic hemoclipping of an esophageal perforation

We describe a case of esophageal perforation that resulted from a fishbone. A 71-year-old man had had a fishbone impacted in the lower esophagus for 2 days. At presentation, the bone was dislodged at endoscopy; one round opening in a deep ulceration was detected when the fishbone was removed. The perforation was closed by endoscopic hemoclipping, after the removal of the fishbone. A thoracic computed tomography revealed air around the esophagus, aorta and bronchus and the presence of a pleural effusion. These findings suggested mediastinal emphysema and mediastinitis due to the esophageal perforation after the removal of the fishbone. Esophagography revealed a focal esophageal defect and linear contrast leakage at the distal esophagus. The mediastinal emphysema and pleural effusion successfully resolved after the endoscopic hemoclip application and conservative management of the perforation.

5-fluorouracil, mitomycin-C, and polysaccharide-K adjuvant chemoimmunotherapy for locally advanced gastric cancer: the prognostic significance of frequent perineural invasion

BACKGROUND/AIMS

Although adjuvant chemotherapy has demonstrated small but significant survival benefit in locally advanced gastric cancer in several meta-analyses, optimal chemotherapy regimen remains to be determined.

METHODOLOGY

We retrospectively analyzed the survival of 207 gastric cancer patients (stage IB: 19, II: 65, IIIA: 58, IIIB: 28, IV: 37) who underwent 5-fluorouracil (5-FU), mitomycin-C (MMC), and polysaccharide-K (PSK) chemoimmunotherapy (CITX) after curative resection (FM group). The survival of FM group was compared with that of historical control cohort of 103 patients with almost identical stage distribution who received 5-FU and doxorubicin-based chemotherapy (FA group).

RESULTS

Five-year disease-free survival and overall survival (OS) of FM group were 58.7% and 59.1%, respectively. Frequent perineural invasion was significantly associated with poor OS (p = 0.01) in multivariate analysis. There was no statistically significant difference in 5-year OS (59.1% vs. 56.2%, p = 0.637) between FM and FA groups. FM group showed superior 5-year OS (84.4% vs. 67.6%, p = 0.019) compared with FA group in stage IB or II patients without significant difference (p = 0.222) in stage IIIA to IV.

CONCLUSIONS

5-FU, MMC, and PSK CITX is as effective as 5-FU and doxorubicin-based chemotherapy. Moreover, frequent perineural invasion seems to be an important poor prognostic factor.

5-fluorouracil, mitomycin-C, and polysaccharide-K adjuvant chemoimmunotherapy for locally advanced gastric cancer: the prognostic significance of frequent perineural invasion

BACKGROUND/AIMS

Although adjuvant chemotherapy has demonstrated small but significant survival benefit in locally advanced gastric cancer in several meta-analyses, optimal chemotherapy regimen remains to be determined.

METHODOLOGY

We retrospectively analyzed the survival of 207 gastric cancer patients (stage IB: 19, II: 65, IIIA: 58, IIIB: 28, IV: 37) who underwent 5-fluorouracil (5-FU), mitomycin-C (MMC), and polysaccharide-K (PSK) chemoimmunotherapy (CITX) after curative resection (FM group). The survival of FM group was compared with that of historical control cohort of 103 patients with almost identical stage distribution who received 5-FU and doxorubicin-based chemotherapy (FA group).

RESULTS

Five-year disease-free survival and overall survival (OS) of FM group were 58.7% and 59.1%, respectively. Frequent perineural invasion was significantly associated with poor OS (p = 0.01) in multivariate analysis. There was no statistically significant difference in 5-year OS (59.1% vs. 56.2%, p = 0.637) between FM and FA groups. FM group showed superior 5-year OS (84.4% vs. 67.6%, p = 0.019) compared with FA group in stage IB or II patients without significant difference (p = 0.222) in stage IIIA to IV.

CONCLUSIONS

5-FU, MMC, and PSK CITX is as effective as 5-FU and doxorubicin-based chemotherapy. Moreover, frequent perineural invasion seems to be an important poor prognostic factor.

Association of aortic plaque with intracranial atherosclerosis in patients with stroke

OBJECTIVE

To determine whether there is a relationship between aortic plaques and intracranial (IC) atherosclerosis.

METHODS

We reviewed 922 patients with stroke who had both transesophageal echocardiography and cerebral angiography. The plaques of these patients were classified as either complex aortic plaques (CAP), which protruded > or =4 mm or were present as mobile lesions in the proximal aorta, or simple aortic plaques (SAP), which were <4 mm or present in the descending aorta. Cerebral artery atherosclerosis was classified as either an IC or extracranial (EC) atherosclerosis.

RESULTS

Among the 922 patients, we found aortic plaques in 237 patients (26%). There were 111 (47%) patients of SAP, 74 (31%) patients with CAP, and 52 (22%) patients that had both SAP and CAP. Angiography showed IC or EC atherosclerosis in 511 patients (55%). The presence of aortic plaques was significantly associated with IC or EC atherosclerosis. The significance appeared to be due to the strong association between the presence of SAP and IC atherosclerosis (51% SAP vs 35% no plaques; odds ratio = 1.94, 95% CI: 1.17 to 3.21). In the multiple logistic regression analysis, SAP were independent predictors of IC atherosclerosis

CONCLUSIONS

The presence of simple aortic plaques may be a marker of advanced vascular disease. Detection of simple aortic plaques during transesophageal echocardiography may have clinical implications because patients with these plaques frequently had concomitant intracranial atherosclerosis, a risk factor for stroke.

Fibronectin induces cell proliferation and inhibits apoptosis in human bronchial epithelial cells: pro-oncogenic effects mediated by PI3-kinase and NF-κB

The extracellular matrix glycoprotein, fibronectin, influences a variety of cellular functions including adhesion, migration, survival, differentiation, and growth. Fibronectin has also been shown to increase the migration and proliferation of human lung carcinoma cells. However, the role of fibronectin in controlling lung airway epithelial cell phenotype remains unknown. Here, we demonstrate that fibronectin stimulates the proliferation of human bronchial epithelial cells (BEAS-2B and 16-HBE). Of note, fibronectin induced the mRNA and protein expression of c-Myc and cyclin D1, while it decreased the expressions of cyclin-dependent kinase inhibitor p21 (WAF-1/CIP1/MDA-6) (p21) and the tumor suppressor gene phosphatase and tensin homolog deleted on chromosome ten (PTEN). Fibronectin also stimulated the phosphorylation of the phosphatidylinositol 3 kinase (PI3-K) downstream signal Akt. The inhibitor of PI3-K, Wortmannin, and anti-alpha5beta1 integrin antibodies abrogated the effect of fibronectin on c-Myc, cyclin D1, p21, and PTEN expression. The stimulatory effect of fibronectin was mediated by nuclear factor kappaB (NF-kappaB) since fibronectin induced the expression of the p65 component of NF-kappaB and enhanced NF-kappaB DNA binding. Furthermore, we found that p65 small interfering RNA inhibited the effect of fibronectin on c-Myc, cyclin D1, p21, PTEN expression, and on fibronectin-induced cell proliferation. Finally, we found that fibronectin inhibits apoptosis by reducing DNA fragmentation and inhibiting the activities of caspases 3/7. Taken together, our findings demonstrate that fibronectin stimulates human bronchial epithelial cell growth and inhibits apoptosis through activation of NF-kappaB, which, in turn, increases the expression of c-Myc and cyclin D1 and decreases p21 and PTEN via alpha5beta1 integrin-dependent signals that include PI3-K/Akt. Therefore, alternations in the extracellular matrix composition of the lung, with increased fibronectin, might promote epithelial cell growth and thereby contribute to oncogenesis in certain settings.

Influence of VEGF gene polymorphisms on the severity of ankylosing spondylitis

OBJECTIVES

To investigate the role of polymorphisms of the vascular endothelial growth factor (VEGF) gene in susceptibility to ankylosing spondylitis (AS), and their relationship to clinical features and radiographic severity.

METHODS

This study included 157 patients with AS and 140 healthy unrelated controls. Polymorphisms of the VEGF gene were analysed by the polymerase chain reaction (PCR)-restriction fragment length polymorphism assay and amplification refractory mutation system-PCR. Haplotypes were reconstructed using the Bayesian algorithm. Radiographic severity was assessed by the Bath Ankylosing Spondylitis Radiological Index (BASRI).

RESULTS

The genotype frequencies of the polymorphisms were in Hardy-Weinberg equilibrium. The distributions of genotypes and alleles did not differ between AS patients and controls. Among the six haplotypes reconstructed based on the tight linkage disequilibrium at positions -2578, -1154 and -634 (pairwise linkage disequilibrium coefficient, r = 0.361-0.706), no haplotype was associated with susceptibility to AS. Clinical features were analysed for the four haplotypes (CGC, CGG, AAG, AGG) which were prevalent. In carriers of the AGG haplotype, the frequency of cervical spine involvement was significantly higher (P = 0.002, P(corr) = 0.036) and that of patients showing a BASRI score >6 was also higher (P = 0.025, P(corr) = 0.45).

CONCLUSIONS

This study demonstrates that polymorphisms of the VEGF gene may contribute to disease severity in AS.