70 research outputs found

    Understanding of matrix embedding: a theoretical spectroscopic study of CO interacting with Ar clusters, surfaces and matrices

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    Through benchmark studies, we explore the performance of PBE density functional theory, with and without Grimme's dispersion correction (DFT-D3), in predicting spectroscopic properties for molecules interacting with rare gas matrices. Here, a periodic-dispersion corrected model of matrix embedding is used for the first time. We use PBE-D3 to determine the equilibrium structures and harmonic vibrational frequencies of carbon monoxide in interaction with small Ar clusters (CO–Arn, n = 1, 2, 3), with an Ar surface and embedded in an Ar matrix. Our results show a converging trend for both the vibrational frequencies and binding energies when going from the gas-phase to a fully periodic approach describing CO embedding in Ar. This trend is explained in terms of solvation effects, as CO is expected to alter the structure of the Ar matrix. Due to a competition between CO–Ar interactions and Ar–Ar interactions, perturbations caused by the presence of CO are found to extend over several Å in the matrix. Accordingly, it is mandatory to fully relax rare gas matrices when studying their interaction with embedded molecules. Moreover, we show that the binding energy per Ar is almost constant (∼−130 cm−1 atom−1) regardless of the environment of the CO molecule. Finally, we show that the concentration of the solute into the cold matrix influences the spectroscopic parameters of molecules embedded into cold matrices. We suggest hence that several cautions should be taken before comparing these parameters to gas phase measurements and to theoretical data of isolated species

    Prognostic value of FBXO39 and ETS-1 but not BMI-1 in Iranian colorectal cancer patients

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    Background: Colorectal cancer (CRC) is one of the most prevalent cancers worldwide. Despite recent progress in diagnosis and treatment, it remains a major health problem and further studies are needed. We here investigated expression profiles of the FBXO39, ETS-1 and BMI-1 genes in CRCs to validate any possible diagnostic/prognostic significance. Material and Methods: Thirty six patients with locally advanced CRC admitted to Hazrate-Rasoul Hospital-Tehran were enrolled. Initially the expression pattern of FBXO39, ETS-1 and BMI-1 genes were determined using RT-PCR in CRC tumor and adjacent normal tissues then real-time RT-PCR was employed to quantify BMI-1 gene expression. Results: FBXO39 expression was restricted to tumor tissues. Interestingly, expression of this gene was detected in all stage-0 tumor samples. There was a significant relation between FBXO39 gene expression and lymph node involvement. The ETS-1 gene was expressed in 66 of all tumor tissues with p-value=0.03 for increase as compared to the adjacent normal samples. In addition, there was a significant relation between ETS-1 gene expression and tumor size and lymph node involvement. RT-PCR demonstrated BMI-1 gene expression in both tumor and normal tissues and quantification by real-time RT-PCR showed no association between BMI-1 levels and CRC clinicopathological features. Conclusion: Expression of FBXO39 and ETS-1 with lymph node involvement may be considered as an alarm for the occurrence of CRC metastasis, and therfore have prognostic value while BMI-1 appears without importance. © 2018 Asian Pacific Organization for Cancer Prevention

    Prognostic value of FBXO39 and ETS-1 but not BMI-1 in Iranian colorectal cancer patients

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    Background: Colorectal cancer (CRC) is one of the most prevalent cancers worldwide. Despite recent progress in diagnosis and treatment, it remains a major health problem and further studies are needed. We here investigated expression profiles of the FBXO39, ETS-1 and BMI-1 genes in CRCs to validate any possible diagnostic/prognostic significance. Material and Methods: Thirty six patients with locally advanced CRC admitted to Hazrate-Rasoul Hospital-Tehran were enrolled. Initially the expression pattern of FBXO39, ETS-1 and BMI-1 genes were determined using RT-PCR in CRC tumor and adjacent normal tissues then real-time RT-PCR was employed to quantify BMI-1 gene expression. Results: FBXO39 expression was restricted to tumor tissues. Interestingly, expression of this gene was detected in all stage-0 tumor samples. There was a significant relation between FBXO39 gene expression and lymph node involvement. The ETS-1 gene was expressed in 66 of all tumor tissues with p-value=0.03 for increase as compared to the adjacent normal samples. In addition, there was a significant relation between ETS-1 gene expression and tumor size and lymph node involvement. RT-PCR demonstrated BMI-1 gene expression in both tumor and normal tissues and quantification by real-time RT-PCR showed no association between BMI-1 levels and CRC clinicopathological features. Conclusion: Expression of FBXO39 and ETS-1 with lymph node involvement may be considered as an alarm for the occurrence of CRC metastasis, and therfore have prognostic value while BMI-1 appears without importance. © 2018 Asian Pacific Organization for Cancer Prevention

    Periodic dispersion-corrected approach for isolation spectroscopy of N2 in an argon environment: Clusters, surfaces, and matrices

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    © 2017 American Chemical Society. Ab initio and Perdew, Burke, and Ernzerhof (PBE) density functional theory with dispersion correction (PBE-D3) calculations are performed to study N 2 -Ar n (n ≤ 3) complexes and N 2 trapped in Ar matrix (i.e., N 2 @Ar). For cluster computations, we used both Møller-Plesset (MP2) and PBE-D3 methods. For N 2 @Ar, we used a periodic-dispersion corrected model for Ar matrix, which consists on a slab of four layers of Ar atoms. We determined the equilibrium structures and binding energies of N 2 interacting with these entities. We also deduced the N 2 vibrational frequency shifts caused by clustering or embedding compared to an isolated N 2 molecule. Upon complexation or embedding, the vibrational frequency of N 2 is slightly shifted, while its equilibrium distance remains unchanged. This is due to the weak interactions between N 2 and Ar within these compounds. Our calculations show the importance of inclusion of dispersion effects for the accurate description of geometrical and spectroscopic parameters of N 2 isolated, in interaction with Ar surfaces, or trapped in Ar matrices

    A new hereditary colorectal cancer network in the Middle East and eastern mediterranean countries to improve care for high-risk families

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    Colorectal cancer (CRC) has a very high incidence in the western world. Data from registries in the Middle East showed that the incidence of CRC is relatively low in these countries. However, these data also showed that CRC incidence has increased substantially over the past three decades and that a high proportion of cases are diagnosed at an early age (<50 years). In view of these findings, more attention should be paid to prevention. Because of the often limited financial resources, focused screening of individuals with hereditary CRC, in particular those with Lynch syndrome, appears to be the most cost-effective strategy. During recent meetings of the Palestinian Society of Gastroenterology and the Mediterranean Task force for Cancer Control (MTCC) in Jericho, and the Patient�s Friends Society of Jerusalem in Hebron the issue of hereditary CRC in the Middle East was discussed and the idea was conceived to establish a network on hereditary colorectal cancer (HCCN-ME) with the goal of improving care for high-risk groups in the Middle East and (Eastern) Mediterranean Countries. © 2017, The Author(s)

    Erratum to: A new hereditary colorectal cancer network in the Middle East and eastern Mediterranean countries to improve care for high-risk families (Familial Cancer, (2018), 17, 2, (209-212), 10.1007/s10689-017-0018-6)

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    Unfortunately, the 10th author name in the author group was published incorrectly in the original publication as �Keivan Maijdzadeh� the correct name is: Keivan Majidzadeh.Author name has also been corrected in the original publication. © Springer Science+Business Media B.V. 2017

    A new hereditary colorectal cancer network in the Middle East and eastern mediterranean countries to improve care for high-risk families

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    Colorectal cancer (CRC) has a very high incidence in the western world. Data from registries in the Middle East showed that the incidence of CRC is relatively low in these countries. However, these data also showed that CRC incidence has increased substantially over the past three decades and that a high proportion of cases are diagnosed at an early age (<50 years). In view of these findings, more attention should be paid to prevention. Because of the often limited financial resources, focused screening of individuals with hereditary CRC, in particular those with Lynch syndrome, appears to be the most cost-effective strategy. During recent meetings of the Palestinian Society of Gastroenterology and the Mediterranean Task force for Cancer Control (MTCC) in Jericho, and the Patient�s Friends Society of Jerusalem in Hebron the issue of hereditary CRC in the Middle East was discussed and the idea was conceived to establish a network on hereditary colorectal cancer (HCCN-ME) with the goal of improving care for high-risk groups in the Middle East and (Eastern) Mediterranean Countries. © 2017, The Author(s)
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