Preparation and Characterization of Tertiary Phosphine Carbonyl Ruthenium (0) Complexes

Dichlorocarbonyltris(triphenylphosphine)ruthenium (II), Ru(CO)(Cl)2(Ph3P)3, was prepared by modification of a procedure reported to yield the dimer, (Ru(CO)(Cl)2(Ph3P)2)2. Dissolution of Ru(CO)(Cl)2(Ph3P)3 in acetonitrile resulted in loss of triphenylphosphine and dimer formation. Metathesis of Ru(CO)(Cl)2(Ph3P)3 in hexane with excess tertiary phosphine yielded complexes of the type Ru(CO)(Cl)2-(R2R′P)3 where R2R′P is Ph2MeP or PhMe2P. 1H and 31p nmr spectra of these materials showed that two phosphines are mutually trans and cis to the remaining phosphine ligand. This metathesis reaction could not be used with tertiary alkyl phosphine to prepare analogous compounds. Potentiostatic reduction of Ru(CO)(Cl)2(Ph3P)3 in acetonitrile with excess Ph3P at a platinum cathode gave the zero valent complex, Ru(CO)(CH3CN)(Ph3P)3, in high yield. This compound has also been synthesized by electrolysis of the dimer mentioned above. The enhanced solubility of Ru(CO)(Cl)2(Ph3P)3 relative to the dimer results in shorter electrolysis times. Attempts to metathesize Ru(CO)(CH3CN)(Ph3P)3 with Ph2MeP, PhMe2P or Et3P in acetonitrile yielded only mixtures of compounds as intractable oils. Polarographic and voltammetric studies of Ru(CO)(Cl)2(Ph2MeP)3 and Ru(CO)(Cl)2(PhMe2P)3 in acetonitrile indicates that these materials are reduced irreversibly with the uptake of two electrons. Two electroactive species are formed in acetonitrile solutions of these compounds. These species arise from tertiary phosphine/acetonitrile exchange. Mass transport of the electroactive speciesis controlled by both kinetics and diffusion

Rating and selecting CRM systems for trade enterprises management

Статья посвящена исследованию современного состояния торговой отрасли Украины, рейтинговой оценке и выбору CRM-систем для управления торговыми предприятиями. Проанализирована динамика структуры экономики Украины за 2010-2017 годы и определено, что за этот период оптовая и розничная торговля была ведущей отраслью экономики Украины, сохраняя в структуре экономики первое место по объему реализованной продукции. Экспертным методом проверено степень согласованности мнений экспертов относительно рейтинга 4-х CRM-систем: bpm online sales, Bitrix24, AmoCRM, Мегаплан. Рассчитан коэффициент конкордации Кендалла, значение χ2-критерия Пирсона свидетельствует о значимости коэффициента конкордации и сильной связи между признаками. Определена наиболее оптимальная CRM-система для управления торговыми предприятиями Украины и предложены пути популяризации использования CRM-систем в торговой отрасли Украины.The article is devoted to the current state study of the Ukrainian trade industry, rating and selecting CRM systems for trade enterprise management. The process of the trade enterprises management determines the need to use information systems and technologies because they can increase the efficiency of enterprises and processes management. This leads to increased sales and profits. However, CRM systems and technologies are not sufficiently used in the Ukrainian trade industry because only 6 percent of enterprises actively used systems for customer relationship management. That’s why the current state analysis of the Ukrainian trade industry, the rating and the selecting CRM systems for the trade enterprises management are relevant and has a great practical importance. The dynamics of Ukraine’s national economy structure for 2010-2017 has been analyzed. It is shown that the relations between the Ukrainian economy sectors change over time and will change in the future. Despite this fact, the wholesale and retail trade ranked first in the structure of the national economy in terms of sales. As the result, the trade industry was a leading branch of the Ukrainian economy during this period. The ratings of CRM systems compiled by authors are very different. Therefore, it is proposed to use an expert method and different sources of information to determine the degree of consistency of expert opinions on this issue. In this study, only those CRM systems that are recognized as major players in Ukraine are used. Thus, a comparative analysis of four CRM systems such as bpm online sales, Bitrix24, AmoCRM, Megaplan was carried out. Kendall concordance coefficient has been calculated. Its value indicates a strong consistency of expert opinions. Then, Pearson's chi-squared test is used to assess the relationship between considered signs. Pearson criterion value indicates the importance of the coefficient of concordance and the strong correlation between the signs. Provided analysis in the article allowed us to determine the most optimal CRM-system for Ukraine’s trade enterprises management. Ways to popularize the use of CRM-systems in the Ukrainian trade industry are proposed

Control Physicochemical Properties of Nanoparticle Surfaces to Modulate Immune-Cell Recruitment to Scaffolds

Although many complex tissue engineering scaffolds have been developed, the number of translated treatments remains stagnant. Successful applications of scaffolds in regenerative medicine often requires scaffolds to elicit minimal host immune response and controlled release of bioactive molecules. Nanoparticles have shown great promise in the controlled release of therapeutics to aid tissue engineering. However, nanoparticles incorporated in tissue engineering scaffolds causes extra inflammatory responses. Although the release of anti-inflammatory drugs has been shown to reduce the foreign body response to scaffolds in vivo, the drugs also interfere with immune cells that are vital for tissue regeneration. Proposed here is a nanoparticle embedded scaffold drug delivery system designed to minimize the host immune response by controlling the physiochemical properties of nanoparticles. This system embeds PLGA nanoparticles with or without encapsulated immunosuppressant drugs in the walls of alginate scaffolds. The effects of surface modification and release of dexamethasone on immune cell recruitment to scaffolds in vivo were explored. Red Blood Cell Membrane (RBCM) coating on PLGA nanoparticles showed a decrease in neutrophil recruitment as well as an increased number of CD4+ T cells in the scaffolds, which are important for tissue regeneration. Our approach is a new strategy in minimizing the induced foreign body inflammatory response of nanoparticles used for tissue regeneration.M.S., Materials Science and Engineering -- Drexel University, 201

BET protein inhibition sensitizes glioblastoma cells to temozolomide treatment by attenuating MGMT expression

Bromodomain and extra-terminal tail (BET) proteins have been identified as potential epigenetic targets in cancer, including glioblastoma. These epigenetic modifiers link the histone code to gene transcription that can be disrupted with small molecule BET inhibitors (BETi). With the aim of developing rational combination treatments for glioblastoma, we analyzed BETi-induced differential gene expression in glioblastoma derived-spheres, and identified 6 distinct response patterns. To uncover emerging actionable vulnerabilities that can be targeted with a second drug, we extracted the 169 significantly disturbed DNA Damage Response genes and inspected their response pattern. The most prominent candidate with consistent downregulation, was the O-6-methylguanine-DNA methyltransferase (MGMT) gene, a known resistance factor for alkylating agent therapy in glioblastoma. BETi not only reduced MGMT expression in GBM cells, but also inhibited its induction, typically observed upon temozolomide treatment. To determine the potential clinical relevance, we evaluated the specificity of the effect on MGMT expression and MGMT mediated treatment resistance to temozolomide. BETi-mediated attenuation of MGMT expression was associated with reduction of BRD4- and Pol II-binding at the MGMT promoter. On the functional level, we demonstrated that ectopic expression of MGMT under an unrelated promoter was not affected by BETi, while under the same conditions, pharmacologic inhibition of MGMT restored the sensitivity to temozolomide, reflected in an increased level of γ-H2AX, a proxy for DNA double-strand breaks. Importantly, expression of MSH6 and MSH2, which are required for sensitivity to unrepaired O6-methylguanine-lesions, was only briefly affected by BETi. Taken together, the addition of BET-inhibitors to the current standard of care, comprising temozolomide treatment, may sensitize the 50% of patients whose glioblastoma exert an unmethylated MGMT promoter

Chromosome 7 gain and DNA hypermethylation at the HOXA10 locus are associated with expression of a stem cell related HOX-signature in glioblastoma.

BACKGROUND: HOX genes are a family of developmental genes that are expressed neither in the developing forebrain nor in the normal brain. Aberrant expression of a HOX-gene dominated stem-cell signature in glioblastoma has been linked with increased resistance to chemo-radiotherapy and sustained proliferation of glioma initiating cells. Here we describe the epigenetic and genetic alterations and their interactions associated with the expression of this signature in glioblastoma. RESULTS: We observe prominent hypermethylation of the HOXA locus 7p15.2 in glioblastoma in contrast to non-tumoral brain. Hypermethylation is associated with a gain of chromosome 7, a hallmark of glioblastoma, and may compensate for tumor-driven enhanced gene dosage as a rescue mechanism by preventing undue gene expression. We identify the CpG island of the HOXA10 alternative promoter that appears to escape hypermethylation in the HOX-high glioblastoma. An additive effect of gene copy gain at 7p15.2 and DNA methylation at key regulatory CpGs in HOXA10 is significantly associated with HOX-signature expression. Additionally, we show concordance between methylation status and presence of active or inactive chromatin marks in glioblastoma-derived spheres that are HOX-high or HOX-low, respectively. CONCLUSIONS: Based on these findings, we propose co-evolution and interaction between gene copy gain, associated with a gain of chromosome 7, and additional epigenetic alterations as key mechanisms triggering a coordinated, but inappropriate, HOX transcriptional program in glioblastoma

Cilengitide in newly diagnosed glioblastoma: biomarker expression and outcome.

Integrins αvβ3 and αvβ5 regulate angiogenesis and invasiveness in cancer, potentially by modulating activation of the transforming growth factor (TGF)-β pathway. The randomized phase III CENTRIC and phase II CORE trials explored the integrin inhibitor cilengitide in patients with newly diagnosed glioblastoma with versus without O6-methylguanine DNA methyltransferase (MGMT) promoter methylation. These trials failed to meet their primary endpoints.Immunohistochemistry was used to assess the levels of the target integrins of cilengitide, αvβ3 and αvβ5 integrins, of αvβ8 and of their putative target, phosphorylation of SMAD2, in tumor tissues from CENTRIC (n=274) and CORE (n=224).αvβ3 and αvβ5 expression correlated well in tumor and endothelial cells, but showed little association with αvβ8 or pSMAD2 levels. In CENTRIC, there was no interaction between the biomarkers and treatment for prediction of outcome. In CORE, higher αvβ3 levels in tumor cells were associated with improved progression-free survival by central review and with improved overall survival in patients treated with cilengitide.Integrins αvβ3, αvβ5 and αvβ8 are differentially expressed in glioblastoma. Integrin levels do not correlate with the activation level of the canonical TGF-β pathway. αvβ3 integrin expression may predict benefit from integrin inhibition in patients with glioblastoma lacking MGMT promoter methylation

Regulation of glucagon secretion by glucose transporter type 2 (glut2) and astrocyte-dependent glucose sensors

Ripglut1;glut2-/- mice have no endogenous glucose transporter type 2 (glut2) gene expression but rescue glucose-regulated insulin secretion. Control of glucagon plasma levels is, however, abnormal, with fed hyperglucagonemia and insensitivity to physiological hypo- or hyperglycemia, indicating that GLUT2-dependent sensors control glucagon secretion. Here, we evaluated whether these sensors were located centrally and whether GLUT2 was expressed in glial cells or in neurons. We showed that ripglut1;glut2-/- mice failed to increase plasma glucagon levels following glucoprivation induced either by i.p. or intracerebroventricular 2-deoxy-D-glucose injections. This was accompanied by failure of 2-deoxy-D-glucose injections to activate c-Fos-like immunoreactivity in the nucleus of the tractus solitarius and the dorsal motor nucleus of the vagus. When glut2 was expressed by transgenesis in glial cells but not in neurons of ripglut1;glut2-/- mice, stimulated glucagon secretion was restored as was c-Fos-like immunoreactive labeling in the brainstem. When ripglut1;glut2-/- mice were backcrossed into the C57BL/6 genetic background, fed plasma glucagon levels were also elevated due to abnormal autonomic input to the alpha cells; glucagon secretion was, however, stimulated by hypoglycemic stimuli to levels similar to those in control mice. These studies identify the existence of central glucose sensors requiring glut2 expression in glial cells and therefore functional coupling between glial cells and neurons. These sensors may be activated at different glycemic levels depending on the genetic background

The DNA methylome of DDR genes and benefit from RT or TMZ in IDH mutant low-grade glioma treated in EORTC 22033.

The optimal treatment for patients with low-grade glioma (LGG) WHO grade II remains controversial. Overall survival ranges from 2 to over 15 years depending on molecular and clinical factors. Hence, risk-adjusted treatments are required for optimizing outcome and quality of life. We aim at identifying mechanisms and associated molecular markers predictive for benefit from radiotherapy (RT) or temozolomide (TMZ) in LGG patients treated in the randomized phase III trial EORTC 22033. As candidate biomarkers for these genotoxic treatments, we considered the DNA methylome of 410 DNA damage response (DDR) genes. We first identified 62 functionally relevant CpG sites located in the promoters of 24 DDR genes, using the LGG data from The Cancer Genome Atlas. Then we tested their association with outcome [progression-free survival (PFS)] depending on treatment in 120 LGG patients of EORTC 22033, whose tumors were mutant for isocitrate dehydrogenase 1 or 2 (IDHmt), the molecular hallmark of LGG. The results suggested that seven CpGs of four DDR genes may be predictive for longer PFS in one of the treatment arms that comprised MGMT, MLH3, RAD21, and SMC4. Most interestingly, the two CpGs identified for MGMT are the same, previously selected for the MGMT-STP27 score that is used to determine the methylation status of the MGMT gene. This score was higher in the LGG with 1p/19q codeletion, in this and other independent LGG datasets. It was predictive for PFS in the TMZ, but not in the RT arm of EORTC 22033. The results support the hypothesis that a high score predicts benefit from TMZ treatment for patients with IDHmt LGG, regardless of the 1p/19q status. This MGMT methylation score may identify patients who benefit from first-line treatment with TMZ, to defer RT for long-term preservation of cognitive function and quality of life

MGMT methylation analysis of glioblastoma on the Infinium methylation BeadChip identifies two distinct CpG regions associated with gene silencing and outcome, yielding a prediction model for comparisons across datasets, tumor grades, and CIMP-status

The methylation status of the O6-methylguanine- DNA methyltransferase (MGMT) gene is an important predictive biomarker for benefit from alkylating agent therapy in glioblastoma. Recent studies in anaplastic glioma suggest a prognostic value for MGMT methylation. Investigation of pathogenetic and epigenetic features of this intriguingly distinct behavior requires accurate MGMT classification to assess high throughput molecular databases. Promoter methylation-mediated gene silencing is strongly dependent on the location of the methylated CpGs,

Phase II Study of Radiotherapy and Temsirolimus versus Radiochemotherapy with Temozolomide in Patients with Newly Diagnosed Glioblastoma without MGMT Promoter Hypermethylation (EORTC 26082).

EORTC 26082 assessed the activity of temsirolimus in patients with newly diagnosed glioblastoma harboring an unmethylated O6 methylguanine-DNA-methyltransferase (MGMT) promoter. Patients (n = 257) fulfilling eligibility criteria underwent central MGMT testing. Patients with MGMT unmethylated glioblastoma (n = 111) were randomized 1:1 between standard chemo-radiotherapy with temozolomide or radiotherapy plus weekly temsirolimus (25 mg). Primary endpoint was overall survival at 12 months (OS12). A positive signal was considered >38 patients alive at 12 months in the per protocol population. A noncomparative reference arm of 54 patients evaluated the assumptions on OS12 in a standard-treated cohort of patients. Prespecified post hoc analyses of markers reflecting target activation were performed. Both therapies were administered per protocol with a median of 13 cycles of maintenance temsirolimus. Median age was 55 and 58 years in the temsirolimus and standard arms, the WHO performance status 0 or 1 for most patients (95.5%). In the per protocol population, 38 of 54 patients treated with temsirolimus reached OS12. The actuarial 1-year survival was 72.2% [95% confidence interval (CI), 58.2-82.2] in the temozolomide arm and 69.6% (95% CI, 55.8-79.9) in the temsirolimus arm [hazard ratio (HR) 1.16; 95% CI, 0.77-1.76; P = 0.47]. In multivariable prognostic analyses of clinical and molecular factors, phosphorylation of mTORSer2448 in tumor tissue (HR 0.13; 95% CI, 0.04-0.47; P = 0.002), detected in 37.6%, was associated with benefit from temsirolimus. Temsirolimus was not superior to temozolomide in patients with an unmethylated MGMT promoter. Phosphorylation of mTORSer2448 in the pretreatment tumor tissue may define a subgroup benefitting from mTOR inhibition. Clin Cancer Res; 22(19); 4797-806. ©2016 AACR