111 research outputs found

    Human adenocarcinoma cell line sensitivity to essential oil phytocomplexes from pistacia species: A multivariate approach

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    Principal component analysis (PCA) multivariate analysis was applied to study the cytotoxic activity of essential oils from various species of the Pistacia genus on human tumor cell lines. In particular, the cytotoxic activity of essential oils obtained from P. lentiscus, P. lentiscus var. chia (mastic gum), P. terebinthus, P. vera, and P. integerrima, was screened on three human adenocarcinoma cell lines: MCF-7 (breast), 2008 (ovarian), and LoVo (colon). The results indicate that all the Pistacia phytocomplexes, with the exception of mastic gum oil, induce cytotoxic effects on one or more of the three cell lines. PCA highlighted the presence of different cooperating clusters of bioactive molecules. Cluster variability among species, and even within the same species, could explain some of the differences seen among samples suggesting the presence of both common and species-specific mechanisms. Single molecules from one of the most significant clusters were tested, but only bornyl-acetate presented cytotoxic activity, although at much higher concentrations (IC50 = 138.5 \ub5g/mL) than those present in the essential oils, indicating that understanding of the full biological effect requires a holistic vision of the phytocomplexes with all its constituents

    Chiral Cyclobutane β-Amino Acid-Based Amphiphiles: Influence of Cis/Trans Stereochemistry on Solution Self-Aggregation and Recognition

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    Novel diastereomeric anionic amphiphiles based on the rigid cyclobutane β-amino acid scaffold have been synthesized and deeply investigated with the aim of generating new functional supramolecular architectures on the basis of the rational design of original amphiphilic molecules and the control of their self-assembly. The main interest has been focused on the effect that cis/trans stereochemistry exerts on their molecular organization and recognition. In diluted solutions, the relative stereochemistry mainly influences the headgroup solvation and anionic-charge stabilization, i.e., better stabilized in the cis diastereoisomer due to intramolecular hydrogen-bonding and/or charge-dipole interactions. This provokes differences in their physicochemical behavior (pKa, cmc, conductivity) as well as in the structural parameters of the spherical micelles formed. Although both diastereoisomers form fibers that evolve with time from the spherical micelles, they display markedly different morphology and kinetics of formation. In the lyotropic liquid crystal domain, the greatest differences are observed at the highest concentrations and can be ascribed to different hydrogen-bonding and molecular packing imposed by the stereochemical constraints. Remarkably, the spherical micelles of the two anionic surfactants show dramatically diverse enantioselection ability for bilirubin enantiomers. In addition, both the surfactants form heteroaggregates with bilirubin at submicellar concentrations but with a different expression of supramolecular chirality. This points out that the unlike relative configuration of the two surfactants influences their chiral recognition ability as well as the fashion in which chirality is expressed at the supramolecular level by controlling the molecular organization in both micellar aggregates and surfactant/bilirubin heteroaggregates. All these differential features can be appropriate and useful for the design and development of new soft materials with predictable and tunable properties and reveal the cyclobutane motif as a valuable scaffold for the preparation of new amphiphiles.We thank Jaume Caelles, in the SAXS-WAXS service at IQAC, for X-Ray measurements, and Imma Carrera for technical assistance in the surface tension measurements. Financial support from MINECO (grants CTQ2010-15408/BQU, CTQ2013-41514-P, and CTQ2013-43754-P) is gratefully acknowledged. Authors also thank the support from Generalitat de Catalunya (2014SGR358 and 2014SGR836).Peer reviewe

    Role of the hydrophobic effect in the transfer of chirality from molecules to complex systems. From chiral surfactants to porphyrin/surfactant aggregates

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    The interaction between the achiral sulfonated porphyrin 5,10,15,20-tetrakis(4-sulfonatophenyl) porphyrin, H2TPPS4, and two chiral cationic surfactants has been studied by optical absorption, fluorescence, and circular dichroism (CD) spectroscopies. At surfactant concentrations above the critical micellar concentration (cmc) the porphyrin is included in the micellar aggregates, but it is CD silent. Below the cmc at a definite porphyrin/surfactant stoichiometry the formation of heteroaggregates with transfer of chirality to the porphyrin chromophore occurs. The preferred surfactant/porphyrin stoichiometry is 3:1, which suggests a structure driven by electrostatic and hydrophobic interactions between porphyrin and surfactant and dipolar and ionic interactions with the water solution. At surfactant concentrations above the cmc, depending on the protocol of preparation of the samples, the formation of the two kinds of aggregates can be observed, reversible for the simple surfactant micelles incorporating the porphyrin, but irreversible for the heteroaggregates

    Crystal structure analyses facilitate understanding of synthesis protocols in the preparation of 6,6′-dibromo-substituted BINOL compounds

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    A combination of crystallographic and spectroscopic techniques has been used in order to address thorough purification protocols for a series of atropisomeric 1,1′-binaphthalene-2,2′-diol (BINOL) derivatives to be used as building blocks for chiral nanoscale constructs

    New chiral polyfunctional cyclobutane derivatives from (-)-verbenone: Possible surfactant behaviour

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    New enantiopure cyclobutane derivatives have been synthesized from a chiral precursor derived from (-)-verbenone. The cyclobutane moiety acts as a chiral platform to afford a γ-amino acid function in a branched side-chain containing an additional stereogenic centre as well as additional C6 or C16-alkyl chains linked to the ring by means of an amine or an amide function. One of these compounds, obtained as a 1:2 mixture with its TFA salt has been investigated, suggesting behaviour as a good surfactant and its critical micellar concentration has been determined. © 2013 Elsevier Ltd. All rights reserved.Imma Carrera is acknowledged for help in the measurement of surface tensions. Jaume Caelles from the SAXS-WAXS service at IQAC is acknowledged for the SAXS measurements. The authors thank financial support from Spanish Ministerio de Ciencia e Innovación (grant CTQ2010-15408/BQU and CTQ2010-14897) and Generalitat de Catalunya (grant 2009SGR-733 and 2009SGR-1331).Peer reviewe

    Emerging Therapeutic Approaches for the Most Aggressive Epithelial Thyroid Cancers

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    The majority of epithelial thyroid carcinomas (TC) have a differentiated (DTC) histotype and include the papillary (PTC) and the follicular (FTC) TC which, ensuing dedifferentiation, generate the aggressive poorly differentiated (PDTC) and anaplastic (ATC) TC. Although derived from the same cell type, each TC shows specific histological features, biological behavior, and degree of differentiation because of different genetic alterations. Total thyroidectomy, followed by adjuvant therapy with 131I, is the treatment of choice for most patients affected by DTC. The prognosis of DTC patients is favorable, with 10‐year survival rate of nearly 90%. However, one third of them face the morbidity of disease recurrence and TC‐related deaths. The worst outcomes are encountered in patients with PDTC and ATC. The latter, in particular, has a mean survival time of few months from the diagnosis, which is not influenced by current anticancer treatments. Following the progress made in the comprehension of the underlying molecular mechanisms deregulated in TC progression, novel therapeutic approaches have come to light. Here, we will attempt to review new targeted therapies, which are currently being exploited in preclinical and clinical studies, with tyrosine kinase inhibitors as well as with emerging inhibitors of mitotic kinases, in PDTC and ATC

    CTLA-4 and PD-1 ligand gene expression in epithelial thyroid cancers

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    The dysregulation of PD-1 ligands (PD-L1 and PD-L2) and CTLA-4 ligands (CD80 and CD86) represents a tumor strategy to escape the immune surveillance. Here, the expression of PD-L1, PD-L2, CD80 and CD86 was evaluated at mRNA level in 94 patients affected by papillary thyroid carcinoma (PTC) and 11 patients affected by anaplastic thyroid carcinoma (ATC). Variations in the mRNAs in PTC patients were then correlated with clinicopathological features. The expression of all genes was deregulated in PTC and ATC tissues compared to normal tissues. In particular, the down-regulation of CD80 was observed in above all ATC. In addition, the increased expression of CD80 associated to longer disease-free survival in PTC. Higher expression of PD-L1 associated with the classical histological variant and with the presence of BRAFV600E mutation in PTC. The increased PD-L2 expression correlated with BRAFV600E mutation and lymph node metastasis, while its lower expression correlated with the follicular PTC variant. The latter was also associated with the CD80 down-regulation, which was also related to the absence of lymph node metastasis. In conclusion, we documented the overall dysregulation of PD-1 and CTLA-4 ligands in PTC and ATC tissues and a possible prognostic value for CD80 gene expression in PTC

    Cyclobutane scaffold in bolaamphiphiles : Effect of diastereoisomerism and regiochemistry on their surface activity aggregate structure

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    Cationic bolaamphiphiles have been synthesized starting from meso cis- or chiral trans-1,2-difunctionalized cyclobutane derivatives. They include cis/trans pairs of diastereoisomers, of N- or C-centered bisamides. The goal of this work was to investigate the influence of stereochemistry and regiochemistry on their abilities as surfactants and self-assembly. Very large differences in surface coverage (2-fold), critical micellar concentration (cmc, up to 2 orders of magnitude), and aggregate structure (from lamellae to fibers) for the four molecules are remarkable due to regio- and stereochemistry differences. Computational calculations were carried out to rationalize the experimental findings and a new methodology has been developed to calculate the structure of these bolaamphiphiles at the surface. Although the four surfactants adopt a wicket-like conformation, for N-centered trans, the distance between polar heads is much larger than that for the other three molecules, as suggested by calculations. We have shown that the interplay between the regiochemistry and stereoisomerism, enhanced by rigidity of the cyclobutane ring, affects different physicochemical properties quite differently. That is, the cmc value is mainly governed by stereochemistry, with regiochemistry only modulating this value. On the other hand, regiochemistry definitely governs the morphology of the supramolecular aggregates (i.e., long fibers versus plates or spherical assemblies), with stereochemistry finely modulating their structural parameters. All these results must help in the rational design of new bolaamphiphiles with predictable properties and useful potential applications

    The effect of pharmacological treatment on ADMA in patients with heart failure.

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    Asymmetric dimethylarginine (ADMA) plays a crucial role in the arginine-nitric oxide (NO) pathway. NO plays an important role in controlling vascular tone and regulates the contractile properties of cardiac myocytes. The purpose of this study was to investigate the effect of pharmacological treatment on asymmetrical dimethylarginine (ADMA) plasma levels in patients with acute congestive heart failure (HF). Patients with symptomatic acute congestive HF (NYHA Class III-IV) and impaired left ventricular (LV) function (ejection fraction less than 40 percent) were included in the study. ADMA and SDMA concentrations were assessed before and after pharmacological treatment in 18 critically ill patients on the intensive care unit by high performance liquid chromatography. All patients received a complete pharmacological treatment (diuretics, digoxin, ACE-inhibitors or angiotensin receptor blockers, and nitroglicerin) for the treatment of acute congestive HF. ADMA plasma levels of critically ill patients were significantly higher after pharmacological treatment respect baseline values (pre-treatment). In critically ill patients with acute congestive HF acute renal impairment function and the modulation of NOS determine plasma ADMA/SDMA levels after therapy

    Increased NK Cell Count in Multiple Sclerosis Patients Treated With Dimethyl Fumarate: A 2-Year Longitudinal Study

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    Background: Dimethyl fumarate (DMF) is a disease-modifying drug for relapsing-remitting multiple sclerosis. Among others, DMF impedes immune activation by shifting the balance between inflammatory and regulatory cell types and by inducing apoptosis-triggered lymphopenia. Although the decrease in lymphocyte count is an early effect of the drug in several patients, the long-term impact on lymphocyte subsets is largely unknown.Methods: We performed a 2-years observational study on total lymphocyte count and subsets thereof by flow cytometry of peripheral blood of 38 multiple sclerosis patients in treatment with DMF. Data were collected at the beginning and after 3, 6, 12, and 24 months of therapy.Results: Total lymphocyte count decreased in relation to time of exposure to DMF. Mean absolute B cell count decreased by 34.1%(p < 0.001) within the first 3months of therapy and then remained stable over time. Mean absolute CD3(+) T cells count decrement reached 47.5% after 12 months of treatment ( p < 0.001). NK cells count showed a heterogeneous trend, increasing by 85.9%( p < 0.001) after 2 years of treatment. CD4(+) T cells and CD8(+) T cells substantially decreased, with a significant increase of CD4(+)/CD8(+) ratio during the first year of therapy.Conclusions: NK cells showed a heterogeneous behavior during DMF treatment with a significant increase over time. Since NK cells may also have a regulatory effect on immune system modulation, their increase during DMF treatment might play a role in the efficacy and safety of the drug
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