104 research outputs found

    The electronic and elasticity properties of new half-metallic chalcogenides Cu(3)TMCh(4) (TM = Cr, Fe and Ch = S, Se, Te): an ab initio study

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    WOS: 000455480300006The ternary copper-based chalcogenides Cu(3)TMCh(4) (TM = Cr, Fe and Ch = S, Se, Te), which have simple cubic (SC) crystal structure and conform to space group with 215 space number, have been investigated by spin-polarised generalised gradient approximation (GGA) in the framework of density functional theory (DFT). All systems have been considered in ferromagnetic (FM) order. The mechanical and thermal properties and the electronic band structures of these systems have been investigated after the well-optimised structural parameters have been obtained. The spin-polarised electronic band structures of all the systems exhibit half-metallic behaviour with band gaps in minority spin channel from 0.29 eV for Cu3FeTe4 to 1.08 eV for Cu3CrS4, while metallic band structures are observed for majority spins. This agrees with the calculated total magnetic moments which are close to integer values. The calculated negative formation enthalpies indicate the energetic and thermodynamic stability of these compounds. Moreover, the calculated elastic constants verify that these materials are stable mechanically due to satisfying Born stability criteria. The estimated anisotropy shear factors show that Cu3FeS4, Cu3FeSe4 and Cu3CrSe4 systems have nearly isotropic character with 1.004, 0.910, and 0.958 values, respectively, whereas other compounds have relatively low anisotropic behaviour.TUBITAK (The Scientific & Technological Research Council of Turkey) through TR-Grid e-Infrastructure ProjectTurkiye Bilimsel ve Teknolojik Arastirma Kurumu (TUBITAK)This research was supported in part by TUBITAK (The Scientific & Technological Research Council of Turkey) through TR-Grid e-Infrastructure Project, part of the calculations have been carried out at ULAKBIM Computer Center

    The investigation of electronic, mechanical and lattice dynamical properties of PdCoX (X=Si and Ge) half-Heusler metallics in , and structural phases: an ab initio study

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    WOS: 000406494900001PdCoX (X=Si and Ge) alloys which are XYZ type half-Heusler alloys and also have face centred cubic MgAgAs-type structure which conforms to space group, have been investigated in different atomic arrangements which are called , and phases, using local spin density approximation in the density functional theory as implemented in VASP (Vienna Ab Initio Simulation Package) software. Both of the alloys are considered in ferromagnetic order. After the investigation of stable structural phase for these alloys, their full structural, electronic, magnetic, mechanical, and dynamical properties have been examined in this structural phase. The calculated electronic band structure and the total electronic density of states of our alloys indicated metallic behaviour. The estimated elastic constants show that these are stable and show anisotropic behaviour mechanically in and phases. Also, the calculated phonon dispersion curves show that PdCoX (X=Si and Ge) alloys are stable dynamically in the same structural phases.Ahi Evran University Research Project UnitAhi Evran University [PYO-KMY.4001.15.001]This work was supported by the Ahi Evran University Research Project Unit [project number PYO-KMY.4001.15.001]

    Original Article Expression of fibroblast growth factor receptor 1, fibroblast growth factor 2, phosphatidyl inositol 3 phosphate kinase and their clinical and prognostic significance in early and advanced stage of squamous cell carcinoma of the lung

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    Abstract: Aim: Non-small cell lung carcinoma is the leading cause of cancer related to death in the world. Squamous cell lung carcinoma (SqCLC) is the second most frequent histological subtype of lung carcinomas. Recently, growth factors, growth factor receptors, and signal transduction system-related gene amplifications and mutations are extensively under investigation to estimate the prognosis and to develop individualized therapies in SqCLC. In this study, besides the signal transduction molecule phosphatidyl inositol-3-phosphate kinase (IP3K) p110α, we explored the expressions of fibroblast growth factor 2 (FGF2) and receptor-1 (FGFR1) in tumor tissue and also their clinical and prognostic significance in patients with early/advanced SqCLC. Materials and methods: From 2005 to 2013, 129 patients (23 early, 106 advanced disease) with a histopathological SqCLC diagnosis were selected from the hospital files of Cukurova University Medical Faculty for this study. Two independent pathologists evaluated FGFR1, FGF2, and PI3K (p110α) expressions in both tumor and stromal tissues from 99 of the patients with sufficient tissue samples, using immunohistochemistry. Considering survival analysis separately for patients with both early and advanced stage diseases, the relationship between the clinical features of the patients and expressions were evaluated by univariate and multivariate analyses. Results: FGFR1 expression was found to be low in 59 (60%) patients and high in 40 (40%) patients. For FGF2; 12 (12%) patients had high, 87 (88%) patients had low expression and for IP3K; 31 (32%) patients had high and 66 (68%) patients had low expressions. In univariate analysis, overall survival (OS) was significantly associated with stage of the disease and the performance status of the patient (P<0.0001 and P<0.001). There was no significant difference in OS of the patients with either low or high expressions of FGFR1, FGF2, and IP3K. When the patients with early or advanced stage disease were separately taken into consideration, the relationship did not differ, either. Any of FGFR1, FGF2 or IP3K expressions was not found predictive for the treatment of early or advanced staged patients. On the other hand, the expressions of both FGFR1 and FGF2 were significantly different with respect to smoking, scar of tuberculosis and scar of radiotherapy (P=0.002; P=0.06 and P=0.05, respectively). Discussion: There has not been identified an effective individualized treatment for SqCLC yet. Therefore, in order to be able to develop such a treatment in the future, it is essential to identify the genetic abnormalities that are responsible for the biological behaviors and carcinogenesis of SqCLC. Although we could not show the prognostic and predictive significance of FGFR1, FGF2 and IP3K expressions in SqCLC, we determined the expression rates of FGFR1, FGF2 and IP3K as a reference for Turkish patients. In conclusion, we want to put some emphasis on the fact that, pulmonary fibrosis which is a late complication of radiotherapy at stage III disease, and the scar of tuberculosis could be associated with FGFR1 and FGF2 expressions

    Interventions for preventing oral mucositis for patients with cancer receiving treatment

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    Interventions for preventing oral mucositis for patients with cancer receiving treatmentTreatment for cancer (including bone marrow transplant) can cause oral mucositis (severe ulcers in the mouth). This painful condition can cause difficulties in eating, drinking and swallowing, and may also be associated with infections which may require the patient to stay longer in hospital. Different strategies are used to try and prevent this condition, and the review of trials found that some of these are effective. Two interventions, cryotherapy (ice chips) and keratinocyte growth factor (palifermin¼) showed some benefit in preventing mucositis. Sucralfate is effective in reducing the severity of mucositis, and a further seven interventions, aloe vera, amifostine, intravenous glutamine, granulocyte‐colony stimulating factor (G‐CSF), honey, laser and antibiotic lozenges containing polymixin/tobramycin/amphotericin (PTA) showed weaker evidence of benefit. These were evaluated in patients with different types of cancer, undergoing different types of cancer treatment. Benefits may be restricted to the disease and treatment combinations evaluated

    Cisplatin plus oral etoposide (EoP) combination is more effective than paclitaxel in patients with advanced breast cancer pretreated with anthracyclines: a randomised phase III trial of Turkish Oncology Group

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    Our objective was to determine whether oral etoposide and cisplatin combination (EoP) is superior to paclitaxel in the treatment of advanced breast cancer (ABC) patients pretreated with anthracyclines. From December 1997 to August 2003, 201 patients were randomised, 100 to EoP and 101 to paclitaxel arms. Four patients in each arm were ineligible. The doses of etoposide and cisplatin were 50 mg p.o. twice a day for 7 days and 70 mg m−2 intravenously (i.v.) on day 1, respectively, and it was 175 mg m−2 on day 1 for paclitaxel. Both treatments were repeated every 3 weeks. A median of four cycles of study treatment was given in both arms. The response rate obtained in the EoP arm was significantly higher (36.3 vs 22.2%; P=0.038). Median response duration was longer for the EoP arm (7 vs 4 months) (P=0.132). Also, time to progression was significantly in favour of the EoP arm (5.5 vs 3.9 months; P=0.003). Median overall survival was again significantly longer in the EoP arm (14 vs 9.5 months; P=0.039). Toxicity profile of both groups was similar. Two patients in each arm were lost due to febrile neutropenia. The observed activity and acceptable toxicity of EoP endorses the employment of this combination in the treatment of ABC following anthracyclines

    Helicobacter pylori regulates iNOS promoter by histone modifications in human gastric epithelial cells. [R. Pero* corresponding author]

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    Inducible nitric oxide synthase (iNOS) expression is altered in gastrointestinal diseases. Helicobacter pylori (Hp) infection may have a critical role in iNOS disregulation. We undertook this study to investigate possible chromatin changes occurring early during iNOS gene activation as a direct consequence of Hp???gastric cells interaction. We show that Hp infection is followed by different expression and chromatin modifications in gastric cells including (1) activation of iNOS gene expression, (2) chromatin changes at iNOS promoter including decreased H3K9 methylation and increased H3 acetylation and H3K4 methylation levels, (3) selective release of methyl-CpG-binding protein 2 from the iNOS promoter. Moreover, we show that Hp-induced activation of iNOS is delayed, but not eliminated, by the treatment with LSD1 inhibitors. Our data suggest a role for specific chromatin-based mechanisms in the control of human iNOS gene expression upon Hp exposure

    The use of recombinant human granulocyte colony-stimulating factor in combination with single or fractionated doses of ifosfamide and doxorubicin in patients with advanced soft tissue sarcoma

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    PubMedID: 8808721Sixty patients with stage III-B and IV soft tissue sarcomas were randomized to receive either ifosfamide 5 g/m2xdx1 and doxorubicin 60 mg/m2xdxl given every 3 weeks (arm A) or ifosfamide 1.8 g/m2xdx5 and doxorubicin 60 mg/m2xdx1 given every 4 weeks (arm B). Recombinant human granulocyte colony-stimulating factor (r-met Hu G-CSF: 250 ”g/m2xd) was applied with a prophylactic intent to patients in arm A only. The response rate was higher in arm A patients (56% versus 33%, p = 0.03). In stage III patients, the complete response rate was significantly higher (53% versus, 13.3%, p = 0.01) and the duration of response was significantly longer in arm A (20 ± 8.2 months versus, 13.4 ± 7 months, p = 0.05). Chemotherapy related myelotoxicity and mucositis were also less frequent in this arm as a result of propylactic r-met Hu G-CSF administration (p = 0.04, p = 0.003). It was concluded that single dose ifosfamide and doxorubicin combinations deserve further investigation under the cover of hematopoietic growth factors, particularly in patients with stage III soft tissue sarcomas

    RISK FACTORS FOR JUVENILE DELINQUENCY A QUALITATIVE SURVEY ABOUT SOCIAL WORKERS OPINION ABOUT RISK FACTORS FOR JUVENILE DELINQUENCY

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    The purpose of this study is to identify the risk factors that according to social workers develop a criminal behavior and to gain more knowledge about this and to further contribute and develop current efforts preventing juvenile delinquency. Our focus is to inspect the views of social workers to see if their perception is consistent with previous research. Research shows that efforts become more effective by having knowledge of risk factors for juvenile delinquency (BrĂ„, 2009). It is therefore considered to be of the utmost importance that social workers have good knowledge of risk factors as they help young people who commit criminal acts. The study's empirical material is based on a qualitative study where interviews have been conducted with social secretaries in two different county municipalities. The analysis of the study material includes previous research, Travis Hirschi's theory of control through social ties (1969), Gottfredson and Hirschi's theory of self-control (1990) and gender theory. The results of the study indicate that social workers’ observations of risk factors for juvenile delinquencyare consistent with previous research. It is also possible to see a clear link between the views of the social workers and the two chosen theories that explains why individuals commit crimes (Hirschi, 1969; Hirschi & Gottfredson, 1990)
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