145 research outputs found
Significant effect of interfacial spin moments in ferromagnet-semiconductor heterojunctions on spin transport in a semiconductor
Using controlled ferromagnet (FM) -semiconductor (SC) interfaces in SC-based lateral spin-valve (LSV) devices, we experimentally study the effect of interfacial spin moments in FM-SC heterojunctions on spin transport in SC. First-principles calculations predict that the spin moment of FM-SC junctions can be artificially reduced by inserting 3d transition metal V, Cr, or Cu atomic layers between FM and SC. When all-epitaxial FM-SC Schottky-tunnel contacts with a 0.4-0.5-nm-thick V, Cr, or Cu interfacial layer are formed, we find that the spin signals in FM-SC LSV devices are significantly decreased at 8 K. When we increase the interfacial spin moment by inserting an ∼0.3-nm-thick Co layer between FM and SC, the spin signals at 8 K are significantly enhanced again. From these experiments, we conclude that the interfacial spin moments at FM-SC interfaces are one of the important factors to achieve large spin signals even in SC-based spintronic devices.T. Naito, R. Nishimura, M. Yamada, A. Masago, Y. Shiratsuchi, Y. Wagatsuma, K. Sawano, R. Nakatani, T. Oguchi, and K. Hamaya, Significant effect of interfacial spin moments in ferromagnet-semiconductor heterojunctions on spin transport in a semiconductor, Phys. Rev. B 105, 195308
Spatial and temporal genetic heterogeneity of epidermal growth factor receptor gene status in a patient with non-small cell lung cancer: a case report
<p>Abstract</p> <p>Introduction</p> <p>To date, an epidermal growth factor receptor-activating mutation is recognized as a genetic hallmark that predicts a good response to treatment with epidermal growth factor receptor tyrosine kinase inhibitor. However, there has been less long-term observation of the mutational status within the same patient. To the best of our knowledge, this is the first case report which illustrates the instability of the genetic status of pulmonary adenocarcinoma cells.</p> <p>Case presentation</p> <p>A 64-year-old Japanese woman with advanced lung adenocarcinoma had been undergoing various anticancer treatments, including epidermal growth factor receptor tyrosine kinase inhibitor, for seven years. She had been receiving locoregional treatment in addition to systemic treatment. She maintained a good performance status until seven years after the initial diagnosis, although she had local and distant recurrences. We analyzed the genetic status of the epidermal growth factor receptor gene in a series of specimens obtained from various tumor-containing lesions throughout the therapeutic period. The results of the genetic analyses clearly showed that the spatial and temporal genetic heterogeneity of the epidermal growth factor receptor gene status originated from an identical tumor ancestor.</p> <p>Conclusions</p> <p>An alternative paradigm to determine a therapeutic strategy for a patient with lung cancer should be considered given the genetic heterogeneity and instability of tumor cells.</p
Molecular profiling of signet ring cell colorectal cancer provides a strong rationale for genomic targeted and immune checkpoint inhibitor therapies
We would like to thank all patients whose samples were used in this study. We are also thankful to the Northern Ireland Biobank and Grampian Biorepository for providing us with tissue blocks and patient data; and Dr HG Coleman (Queen’s University Belfast) for her advice on statistical analyses. This work has been carried out with financial support from Cancer Research UK (grant: C11512/A18067), Experimental Cancer Medicine Centre Network (grant: C36697/A15590 from Cancer Research UK and the NI Health and Social Care Research and Development Division), the Sean Crummey Memorial Fund and the Tom Simms Memorial Fund. The Northern Ireland Biobank is funded by HSC Research and Development Division of the Public Health Agency in Northern Ireland and Cancer Research UK through the Belfast CRUK Centre and the Northern Ireland Experimental Cancer Medicine Centre; additional support was received from Friends of the Cancer Centre. The Northern Ireland Molecular Pathology Laboratory which is responsible for creating resources for the Northern Ireland Biobank has received funding from Cancer Research UK, Friends of the Cancer Centre and Sean Crummey Foundation.Peer reviewedPublisher PD
Genotypes and haplotypes of the VEGF gene and survival in locally advanced non-small cell lung cancer patients treated with chemoradiotherapy
<p>Abstract</p> <p>Background</p> <p>Vascular endothelial growth factor (VEGF) is a major mediator of angiogenesis involving in carcinogenesis, including lung cancer. We hypothesized that <it>VEGF </it>polymorphisms may affect survival outcomes among locally advanced non-small cell lung cancer (LA-NSCLC) patients.</p> <p>Methods</p> <p>We genotyped three potentially functional <it>VEGF </it>variants [-460 T > C (rs833061), -634 G > C (rs2010963), and +936 C > T (rs3025039)] and estimated haplotypes in 124 Caucasian patients with LA-NSCLC treated with definitive radiotherapy. We used Kaplan-Meier log-rank tests, and Cox proportional hazard models to evaluate the association between <it>VEGF </it>variants and overall survival (OS).</p> <p>Results</p> <p>Gender, Karnofsky's performance scores (KPS) and clinical stage seemed to influence the OS. The variant C genotypes were independently associated with significantly improved OS (CT+CC vs. TT: adjusted hazard ratio [HR] = 0.58; 95% confidence interval [CI] = 0.37-0.92, <it>P </it>= 0.022), compared with the <it>VEGF </it>-460 TT genotype.</p> <p>Conclusions</p> <p>Our study suggests that <it>VEGF </it>-460 C genotypes may be associated with a better survival of LA-NSCLC patients after chemoradiotherapy. Large studies are needed to confirm our findings.</p
Global Distribution of Human-Associated Fecal Genetic Markers in Reference Samples from Six Continents
Numerous bacterial genetic markers are available for the molecular detection of human sources of fecal pollution in environmental waters. However, widespread application is hindered by a lack of knowledge regarding geographical stability, limiting implementation to a small number of well-characterized regions. This study investigates the geographic distribution of five human-associated genetic markers (HF183/BFDrev, HF183/BacR287, BacHum-UCD, BacH, and Lachno2) in municipal wastewaters (raw and treated) from 29 urban and rural wastewater treatment plants (750-4»400»000 population equivalents) from 13 countries spanning six continents. In addition, genetic markers were tested against 280 human and nonhuman fecal samples from domesticated, agricultural and wild animal sources. Findings revealed that all genetic markers are present in consistently high concentrations in raw (median log10 7.2-8.0 marker equivalents (ME) 100 mL-1) and biologically treated wastewater samples (median log10 4.6-6.0 ME 100 mL-1) regardless of location and population. The false positive rates of the various markers in nonhuman fecal samples ranged from 5% to 47%. Results suggest that several genetic markers have considerable potential for measuring human-associated contamination in polluted environmental waters. This will be helpful in water quality monitoring, pollution modeling and health risk assessment (as demonstrated by QMRAcatch) to guide target-oriented water safety management across the globe.Fil: Mayer, René E.. Vienna University of Technology; Austria. Interuniversity Cooperation Centre for Water and Health; AustriaFil: Reischer, Georg. Vienna University of Technology; AustriaFil: Ixenmaier, Simone K.. Vienna University of Technology; Austria. Interuniversity Cooperation Centre for Water and Health; AustriaFil: Derx, Julia. Vienna University of Technology; AustriaFil: Blaschke, Alfred Paul. Vienna University of Technology; AustriaFil: Ebdon, James E.. University of Brighton; Reino UnidoFil: Linke, Rita. Vienna University of Technology; Austria. Interuniversity Cooperation Centre Water And Health; AustriaFil: Egle, Lukas. Vienna University of Technology; AustriaFil: Ahmed, Warish. Csiro Land And Water; AustraliaFil: Blanch, Anicet R.. Universidad de Barcelona; EspañaFil: Byamukama, Denis. Makerere University; UgandaFil: Savill, Marion. Affordable Water Limited;Fil: Mushi, Douglas. Sokoine University Of Agriculture; TanzaniaFil: Cristobal, Hector Antonio. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Salta. Instituto de Investigaciones para la Industria Química. Universidad Nacional de Salta. Facultad de Ingeniería. Instituto de Investigaciones para la Industria Química; ArgentinaFil: Edge, Thomas A.. Canada Centre for Inland Waters. Environment and Climate Change Canada; CanadáFil: Schade, Margit A.. Bavarian Environment Agency; AlemaniaFil: Aslan, Asli. Georgia Southern University; Estados UnidosFil: Brooks, Yolanda M.. Michigan State University; Estados UnidosFil: Sommer, Regina. Interuniversity Cooperation Centre Water And Health; Austria. Medizinische Universitat Wien; AustriaFil: Masago, Yoshifumi. Tohoku University; JapónFil: Sato, Maria I.. Cia. Ambiental do Estado de Sao Paulo. Departamento de Análises Ambientais; BrasilFil: Taylor, Huw D.. University of Brighton; Reino UnidoFil: Rose, Joan B.. Michigan State University; Estados UnidosFil: Wuertz, Stefan. Nanyang Technological University. Singapore Centre for Environmental Life Sciences Engineering and School of Civil and Environmental Engineering; SingapurFil: Shanks, Orin. U.S. Environmental Protection Agency; Estados UnidosFil: Piringer, Harald. Vrvis Research Center; AustriaFil: Mach, Robert L.. Vienna University of Technology; AustriaFil: Savio, Domenico. Karl Landsteiner University of Health Sciences; AustriaFil: Zessner, Matthias. Vienna University of Technology; AustriaFil: Farnleitner, Andreas. Vienna University of Technology; Austria. Interuniversity Cooperation Centre Water And Health; Austria. Karl Landsteiner University of Health Sciences; Austri
The impact of polymorphic variations in the 5p15, 6p12, 6p21 and 15q25 loci on the risk and prognosis of Portuguese patients with non-small cell lung cancer
Polymorphic variants in the 5p15, 6p12, 6p21, and 15q25 loci were demonstrated to potentially contribute to lung cancer carcinogenesis. Therefore, this study was performed to assess the role of those variants in non-small cell lung cancer (NSCLC) risk and prognosis in a Portuguese population.
MATERIALS AND METHODS:
Blood from patients with NSCLC was prospectively collected. To perform an association study, DNA from these patients and healthy controls were genotyped for a panel of 19 SNPs using a Sequenom® MassARRAY platform. Kaplan-Meier curves were used to assess the overall survival (OS) and progression-free survival (PFS).
RESULTS:
One hundred and forty-four patients with NSCLC were successfully consecutively genotyped for the 19 SNPs. One SNP was associated with NSCLC risk: rs9295740 G/A. Two SNPs were associated with non-squamous histology: rs3024994 (VEGF intron 2) T/C and rs401681 C/T. Three SNPs were associated with response rate: rs3025035 (VEGF intron 7) C/T, rs833061 (VEGF -460) C/T and rs9295740 G/A. One SNP demonstrated an influence on PFS: rs401681 C/T at 5p15, p?=?0.021. Four SNPs demonstrated an influence on OS: rs2010963 (VEGF +405 G/C), p?=?0.042; rs3025010 (VEGF intron 5 C/T), p?=?0.047; rs401681 C/T at 5p15, p?=?0.046; and rs31489 C/A at 5p15, p?=?0.029.
CONCLUSIONS:
Our study suggests that SNPs in the 6p12, 6p21, and 5p15 loci may serve as risk, predictive and prognostic NSCLC biomarkers. In the future, SNPs identified in the genomes of patients may improve NSCLC screening strategies and therapeutic management as well.This project was supported by Programa Doutoral em Medicina e Oncologia Molecular, University of Porto, Porto, Portugal and University of Minho, Braga, Portugal. The funders had no role in study design, data collection and analysis, decision to publish, or preparation of the manuscript
Genome Haploidisation with Chromosome 7 Retention in Oncocytic Follicular Thyroid Carcinoma
Contains fulltext :
108012.pdf (publisher's version ) (Open Access)BACKGROUND: Recurrent non-medullary thyroid carcinoma (NMTC) is a rare disease. We initially characterized 27 recurrent NMTC: 13 papillary thyroid cancers (PTC), 10 oncocytic follicular carcinomas (FTC-OV), and 4 non-oncocytic follicular carcinomas (FTC). A validation cohort composed of benign and malignant (both recurrent and non-recurrent) thyroid tumours was subsequently analysed (n = 20). METHODS: Data from genome-wide SNP arrays and flow cytometry were combined to determine the chromosomal dosage (allelic state) in these tumours, including mutation analysis of components of PIK3CA/AKT and MAPK pathways. RESULTS: All FTC-OVs showed a very distinct pattern of genomic alterations. Ten out of 10 FTC-OV cases showed near-haploidisation with or without subsequent genome endoreduplication. Near-haploidisation was seen in 5/10 as extensive chromosome-wide monosomy (allelic state [A]) with near-haploid DNA indices and retention of especially chromosome 7 (seen as a heterozygous allelic state [AB]). In the remaining 5/10 chromosomal allelic states AA with near diploid DNA indices were seen with allelic state AABB of chromosome 7, suggesting endoreduplication after preceding haploidisation. The latter was supported by the presence of both near-haploid and endoreduplicated tumour fractions in some of the cases. Results were confirmed using FISH analysis. Relatively to FTC-OV limited numbers of genomic alterations were identified in other types of recurrent NMTC studied, except for chromosome 22q which showed alterations in 6 of 13 PTCs. Only two HRAS, but no mutations of EGFR or BRAF were found in FTC-OV. The validation cohort showed two additional tumours with the distinct pattern of genomic alterations (both with oncocytic features and recurrent). CONCLUSIONS: We demonstrate that recurrent FTC-OV is frequently characterised by genome-wide DNA haploidisation, heterozygous retention of chromosome 7, and endoreduplication of a near-haploid genome. Whether normal gene dosage on especially chromosome 7 (containing EGFR, BRAF, cMET) is crucial for FTC-OV tumour survival is an important topic for future research. MICROARRAYS: Data are made available at GEO (GSE31828)
Experimental pressure-temperature phase diagram of boron: resolving the long-standing enigma
Boron, discovered as an element in 1808 and produced in pure form in 1909, has still remained the last elemental material, having stable natural isotopes, with the ground state crystal phase to be unknown. It has been a subject of long-standing controversy, if α-B or β-B is the thermodynamically stable phase at ambient pressure and temperature. In the present work this enigma has been resolved based on the α-B-to- β-B phase boundary line which we experimentally established in the pressure interval of ∼4 GPa to 8 GPa and linearly extrapolated down to ambient pressure. In a series of high pressure high temperature experiments we synthesised single crystals of the three boron phases (α-B, β-B, and γ-B) and provided evidence of higher thermodynamic stability of α-B. Our work opens a way for reproducible synthesis of α-boron, an optically transparent direct band gap semiconductor with very high hardness, thermal and chemical stability
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