RESUMEN
Latin American societies show lower levels of political trust when compared to other regions of the world. The lack of trust in institutions can led to ineffective management of public affairs, social crises, lack of transparency, economic problems and even difficulties in countering pandemics. The objective of this work is to build an index (LADI) that provides a measure of the level of perceived distrust in the institutions of the different Latin American countries and its variations over the period from 2008 to 2018. The data used for this analysis are of a subjective nature and come from the series of surveys provided by Latinobarómetro. To develop the analysis, we have used a quantitative approach of a partially non-compensatory aggregative type, known as Adjusted Mazziotta and Pareto Index. The results show a generalized increase of distrust in the years 2017 and 2018 for several Latin American countries. On the other hand, in countries where the rule of law is more consolidated, a best perception of the functioning of democracy emerges.
RESUMEN
In a previous work I tried to show how a parent's traumatic experiences can weigh on the following generations, approaching these phenomena in terms of introjection and incorporation. Traumatized patients who inherited such burdens suffered a block of their vital abilities, and are then challenged to later acquire the ability to symbolize what had remained unelaborated by previous generations. Accidental impressions, foreign to the patient's story, possibly a result of a certain pre-understanding of the patient's unconscious communications, emerge in countertransference and may reveal hitherto unexpressed dimensions, dissociated psychic areas of the patient.
Asunto(s)
Contratransferencia , Emociones , Terapia Psicoanalítica/métodos , Inconsciente en Psicología , Comunicación , HumanosRESUMEN
The cognate docking performance of Glide was evaluated using the Astex diverse set. The standard Glide SP protocol obtained a 85.7 % success rate when the shape similarity cutoff was set to 0.625. The analysis of docking failures pointed out that, when the SiteMap binding site exposure is less than 0.491, 51 out of 52 ligands are correctly positioned. In light of this important finding, an improved docking protocol called GLIMPSED was set up. GLIMPSED relies on the standard Glide SP protocol for binding sites with low exposure, while a more accurate sampling of docking poses followed by a final MM-GBSA rescoring is performed for those highly exposed to the solvent. GLIMPSED and Glide SP were compared applying an accurate and rigorous metrics described in the literature by Hawkins etâ al. As a result, GLIMPSED was able to dock 89.3 % of the ligands in a correct way. Even though this number is not remarkably different from that obtained with the standard method, it is indeed statistically significant. Applying the Cohen's effect size test, a small, but not trivial, superiority of GLIMPSED was found with respect to standard Glide SP protocol. In our view the SiteMap binding site exposure parameter should be used as guideline to decide whether either a standard or a more extended docking protocol has to be adopted to predict good binding poses.
Asunto(s)
Proteínas/química , Proteínas/metabolismo , Algoritmos , Sitios de Unión/fisiología , Ligandos , Modelos Moleculares , Simulación del Acoplamiento Molecular/métodos , Unión Proteica/fisiología , Programas InformáticosRESUMEN
A series of 3-aryl-naphtho[2,3-d]isoxazole-4,9-diones and some of their 6-aza analogues were synthesized and found to inhibit the heat shock protein 90 (Hsp90). The compounds were tested for their binding to Hsp90 and for their effects on Hsp90 client proteins expression in a series of human tumour cell lines. Representative compounds (7f, 10c) downregulated the Hsp90 client proteins EGFR, Akt, Cdk4, Raf-1, and survivin, and upregulated Hsp70. Most of the compounds, in particular the alkylated 3-pyridyl derivatives, exhibited potent antiproliferative activity, down to two-digit nanomolar range. Preliminary results indicated in vivo activity of 7f against human epithelial carcinoma A431 model growing as tumour xenograft in nude mice, thus supporting the therapeutic potential of this novel series of Hsp90 inhibitors.
Asunto(s)
Antineoplásicos/química , Antineoplásicos/farmacología , Proteínas HSP90 de Choque Térmico/antagonistas & inhibidores , Isoxazoles/química , Naftoquinonas/química , Naftoquinonas/farmacología , Animales , Antineoplásicos/síntesis química , Línea Celular Tumoral , Femenino , Proteínas HSP90 de Choque Térmico/química , Humanos , Concentración 50 Inhibidora , Ratones , Modelos Moleculares , Naftoquinonas/síntesis química , Conformación Proteica , Relación Estructura-Actividad Cuantitativa , Ensayos Antitumor por Modelo de XenoinjertoRESUMEN
A structural investigation on the isoxazole scaffold led to the discovery of 3,4-isoxazolediamide compounds endowed with potent Hsp90 inhibitory properties. We have found that compounds possessing a nitrogen atom directly attached to the C-4 heterocycle ring possess in vitro Hsp90 inhibitory properties at least comparable to those of the structurally related 4,5-diarylisoxazole derivatives. A group of compounds from this series of diamides combine potent binding affinity and cell growth inhibitory activity in both series of alkyl- and aryl- or heteroarylamides, with IC50 in the low nanomolar range. The 3,4-isoxazolediamides were also very effective in causing dramatic depletion of the examined client proteins and, as expected for the Hsp90 inhibitors, always induced a very strong increase in the expression levels of the chaperone Hsp70. In vivo studies against human epidermoid carcinoma A431 showed an antitumor effect of morpholine derivative 73 comparable to that induced by the reference compound 10.
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Amidas/síntesis química , Antineoplásicos/síntesis química , Proteínas HSP90 de Choque Térmico/antagonistas & inhibidores , Isoxazoles/síntesis química , Resorcinoles/síntesis química , Amidas/química , Amidas/farmacología , Animales , Antineoplásicos/química , Antineoplásicos/farmacología , Línea Celular Tumoral , Proliferación Celular/efectos de los fármacos , Cristalografía por Rayos X , Ensayos de Selección de Medicamentos Antitumorales , Femenino , Humanos , Isoxazoles/química , Isoxazoles/farmacología , Ratones , Ratones Desnudos , Modelos Moleculares , Trasplante de Neoplasias , Conformación Proteica , Resorcinoles/química , Resorcinoles/farmacología , Relación Estructura-Actividad , Trasplante HeterólogoRESUMEN
Preliminary studies of historical sources and remote sensing were used to identify ancient olive trees near archaeological sites and heritage buildings in the Orcia Valley (Siena, Italy). Distinctive characters were assessed by traditional pomological observation. Trees with similar characters were selected on the basis of the features of endocarps, the only structure that survives aerobic deterioration and conserves useful botanical information for centuries. Non-invasive morphometric analysis of endocarp size and shape established morphological variations in individuals of different populations. Plastid organization in the endocarp and location of DNA in the endocarp tegument were detected by morphological and ultrastructural observations using light and electron microscopy. Cytoplasmic markers with high polymorphism were used to test similarity of endocarp and leaf DNA within individuals and to confirm low variability and minimal divergence between individuals. The ancient trees studied showed the same allelic profiles and therefore belonged to a distinct cultivar. The traditional pomological descriptions of the trees, leaves and fruits, morphometric analysis of size, and shape elliptic Fourier analysis of endocarp outline, ultrastructural observations and allelic profiles of endocarp tegument delineated the general species-specific qualities of the cultivar "olivastra Seggianese" of the Orcia Valley.
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Olea/fisiología , Alelos , Arqueología , Citoplasma/química , ADN de Plantas/genética , Análisis de Fourier , Italia , Modelos Biológicos , Olea/genética , Olea/ultraestructura , Hojas de la Planta/citología , Hojas de la Planta/metabolismo , Hojas de la Planta/ultraestructura , Polimorfismo Genético , Tecnología de Sensores Remotos , Semillas/química , Semillas/ultraestructuraRESUMEN
Nonpeptidic chiral macrocycles were designed on the basis of an analogue of suberoylanilide hydroxamic acid (2) (SAHA, vorinostat) and evaluated against 11 histone deacetylase (HDAC) isoforms. The identification of critical amino acid residues highly conserved in the cap region of HDACs guided the design of the suberoyl-based macrocycles, which were expected to bear a maximum common substructure required to target the whole HDAC panel. A nanomolar HDAC inhibitory profile was observed for several compounds, which was comparable, if not superior, to that of 2. A promising cytotoxic activity was found for selected macrocycles against lung and colon cancer cell lines. Further elaboration of selected candidates led to compounds with an improved selectivity against HDAC6 over the other isozymes. Pair-fitting analysis was used to compare one of the best candidates with the natural tetrapeptide apicidin, in an effort to define a general pharmacophore that might be useful in the design of surrogates of peptidic macrocycles as potent and isoform-selective inhibitors.
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Inhibidores de Histona Desacetilasas/química , Inhibidores de Histona Desacetilasas/farmacología , Compuestos Macrocíclicos/química , Compuestos Macrocíclicos/farmacología , Línea Celular Tumoral , Diseño de Fármacos , Inhibidores de Histona Desacetilasas/síntesis química , Humanos , Compuestos Macrocíclicos/síntesis química , Modelos MolecularesRESUMEN
The inhibitory activity of an ω-alkoxy analogue of the HDAC inhibitor, Vorinostat (SAHA), against the 11 isoforms of HDAC is described and evaluated with regard to structural biology information retrieved through computational methods. Preliminary absorption and metabolism studies were performed, which positioned this compound as a potential candidate for further preclinical studies and delineated measures for improving its pharmacokinetic profile.
RESUMEN
The ultrastructure of Vitis vinifera seeds from different archaeological sites was studied. Preservation status differed between sites. Preliminary investigations of grape seeds from Poggio Bacherina (Chianciano Terme, Siena) and Miranduolo (Chiusdino, Siena) showed collapsed or charred tegument, making this material suitable for morphometric studies only. Rapid-freeze fixation and substitution of grape seeds from Shahr-I Sokhta in Iran and via De' Castellani in Florence revealed well preserved tegument suitable for chemical and cytochemical analysis. Energy dispersive X-ray microanalysis was used to determine chemical composition. Cytochemical analysis based on fluorescent staining with DAPI suggested the presence of cytoplasm residues.
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Semillas/ultraestructura , Vitis/ultraestructura , Criopreservación/métodosRESUMEN
With the aim of understanding the influence of fluorine on the double bond of the cis-stilbene moiety of combretastatin derivatives and encouraged by a preliminary molecular modeling study showing a different biological environment on the interaction site with tubulin, we prepared, through various synthetic approaches, a small library of compounds in which one or both of the olefinic hydrogens were replaced with fluorine. X-ray analysis on the difluoro-CA-4 analogue demonstrated that the spatial arrangement of the molecule was not modified, compared to its nonfluorinated counterpart. SAR analysis confirmed the importance of the cis-stereochemistry of the stilbene scaffold. Nevertheless, some unpredicted results were observed on a few trans-fluorinated derivatives. The position of a fluorine atom on the double bond may affect the inhibition of tubulin polymerization and cytotoxic activity of these compounds.
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Antineoplásicos/síntesis química , Bibencilos/síntesis química , Flúor , Estilbenos/síntesis química , Animales , Antineoplásicos/química , Antineoplásicos/farmacología , Bibencilos/química , Bibencilos/farmacología , Biopolímeros , Bovinos , Línea Celular Tumoral , Células Cultivadas , Cristalografía por Rayos X , Ensayos de Selección de Medicamentos Antitumorales , Células Endoteliales/citología , Células Endoteliales/efectos de los fármacos , Humanos , Microcirculación/citología , Microtúbulos/efectos de los fármacos , Microtúbulos/metabolismo , Microtúbulos/ultraestructura , Estereoisomerismo , Estilbenos/química , Estilbenos/farmacología , Relación Estructura-Actividad , Tubulina (Proteína)/metabolismoRESUMEN
We describe the design and synthesis of a peptidomimetic library derived from the heptapeptide Ac-RDVLPGT-NH 2, belonging to the Toll/IL-1 receptor (TIR) domain of the adaptor protein MyD88 and effective in inhibiting its homodimerization. The ability of the peptidomimetics to inhibit protein-protein interaction was assessed by yeast 2-hybrid assay and further validated in a mammalian cell system by evaluating the inhibition of NF-kappaB activation, a transcription factor downstream of MyD88 signaling pathway that allows production of essential effector molecules for immune and inflammatory responses.
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Factor 88 de Diferenciación Mieloide/antagonistas & inhibidores , Oligopéptidos/síntesis química , Línea Celular , Humanos , Modelos Moleculares , Imitación Molecular , Factor 88 de Diferenciación Mieloide/química , Factor 88 de Diferenciación Mieloide/genética , FN-kappa B/metabolismo , Oligopéptidos/química , Oligopéptidos/farmacología , Estructura Terciaria de Proteína , Receptores de Interleucina-1/química , Receptores de Interleucina-1/metabolismo , Saccharomyces cerevisiae/genética , Saccharomyces cerevisiae/metabolismo , Transducción de Señal , Estereoisomerismo , Relación Estructura-Actividad , Receptores Toll-Like/química , Receptores Toll-Like/metabolismo , Técnicas del Sistema de Dos HíbridosRESUMEN
Myeloid differentiation factor 88 (MyD88) plays a crucial role in the signaling pathways triggered by interleukin (IL)-1 and Toll-like receptors in several steps of innate host defense. A crucial event in this signaling pathway is represented by dimerization of MyD88, which allows the recruitment of downstream kinases like IRAK-1 and IRAK-4. Herein, we have investigated the function of the Toll/IL-1 receptor (TIR) domain in MyD88 homodimerization in cell-free and in vitro experimental settings by using epta-peptides that mimic the BB-loop region of the conserved TIR domain of different proteins. By using a pull-down assay with purified glutathione S-transferase-MyD88 TIR or co-immunoprecipitation experiments, we found that epta-peptides derived from the TIR domain of MyD88 and IL-18R are the most effective in inhibiting homodimerization with either the isolated TIR or full-length MyD88. Moreover, we demonstrated that a cell permeable analog of MyD88 epta-peptide inhibits homodimerization of MyD88 TIR domains in an in vitro cell system and significantly reduces IL-1 signaling, as assayed by activation of the downstream transcription factor NF-kappaB. Our results indicate that the BB-loop in TIR domain of MyD88 is a good target for specific inhibition of MyD88-mediated signaling in vivo.
Asunto(s)
Antígenos de Diferenciación/metabolismo , Interleucina-1/metabolismo , FN-kappa B/metabolismo , Péptidos/metabolismo , Receptores Inmunológicos/metabolismo , Proteínas Adaptadoras Transductoras de Señales , Secuencia de Aminoácidos , Proteína con Homeodominio Antennapedia , Antígenos de Diferenciación/genética , Dimerización , Proteínas de Homeodominio/genética , Proteínas de Homeodominio/metabolismo , Glicoproteínas de Membrana/genética , Datos de Secuencia Molecular , Factor 88 de Diferenciación Mieloide , Proteínas Nucleares/genética , Proteínas Nucleares/metabolismo , Estructura Terciaria de Proteína , Receptores de Superficie Celular/genética , Receptores Inmunológicos/genética , Receptores de Interleucina-1/genética , Alineación de Secuencia , Receptores Toll-Like , Factores de Transcripción/genética , Factores de Transcripción/metabolismoRESUMEN
We present a combined computational study aimed at identifying the three-dimensional structural properties required for different classes of compounds to show antagonistic activity toward the A(1) adenosine receptor (AR). Particularly, an approach combining pharmacophore mapping, molecular alignment, and pseudoreceptor generation was applied to derive a hypothesis of the interaction pathway between a set of A(1) AR antagonists taken from the literature and a model of the putative A(1) receptor. The pharmacophore model consists of seven features and represents an improvement of the N(6)-C8 model, generally reported as the most probable pharmacophore model for A(1) AR agonists and antagonists. It was used to build up a pseudoreceptor model able to rationalize the relationships between structural properties and biological data of, and external to, the training set. In fact, to further assess its statistical significance and predictive power, the pseudoreceptor was employed to predict the free energy of binding associated with compounds constituting a test set. While part of these molecules was also taken from the literature, the remaining compounds were designed and synthesized by our research group. All of the new compounds were tested for their affinity toward A(1), A(2a), and A(3) AR, showing interesting antagonistic activity and A(1) selectivity.
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Antagonistas de Receptores Purinérgicos P1 , Piridinas/síntesis química , Receptores Purinérgicos P1/química , Animales , Unión Competitiva , Bovinos , Corteza Cerebral/metabolismo , Ligandos , Modelos Moleculares , Piridinas/química , Piridinas/farmacología , Ensayo de Unión Radioligante , Receptores Purinérgicos P1/metabolismo , Relación Estructura-ActividadRESUMEN
The synthesis, anti-Candida activity, and quantitative structure-activity relationship (QSAR) studies of a series of 2,4-dichlorobenzylimidazole derivatives having a phenylpyrrole moiety (related to the antibiotic pyrrolnitrin) in the alpha-position are reported. A number of substituents on the phenyl ring, ranging from hydrophobic (tert-butyl, phenyl, or 1-pyrrolyl moiety) to basic (NH(2)), polar (CF(3), CN, SCH(3), NO(2)), or hydrogen bond donors and acceptor (OH) groups, were chosen to better understand the interaction of these compounds with cytochrome P450 14-alpha-lanosterol demethylase (P450(14DM)). Finally, the triazole counterpart of one of the imidazole compounds was synthesized and tested to investigate influence of the heterocyclic ring on biological activity. The in vitro antifungal activities of the newly synthesized azoles 10p-v,x-c' were tested against Candida albicans and Candida spp. at pH 7.2 and pH 5.6. A CoMFA model, previously derived for a series of antifungal agents belonging to chemically diverse families related to bifonazole, was applied to the new products. Because the results produced by this approach were not encouraging, Catalyst software was chosen to perform a new 3D-QSAR study. Catalyst was preferred this time because of the possibility of considering each compound as a collection of energetically reasonable conformations and of considering alternative stereoisomers. The pharmacophore model developed by Catalyst, named HYPO1, showed good performances in predicting the biological activity data, although it did not exhibit an unequivocal preference for one enantiomeric series of inhibitors relative to the other. One aromatic nitrogen with a lone pair in the ring plane (mapped by all of the considered compounds) and three aromatic ring features were recognized to have pharmacophoric relevance, whereas neither hydrogen bond acceptor nor hydrophobic features were found. These findings confirmed that the key interaction of azole antifungals with the demethylase enzyme is the coordination bond to the iron ion of the porphyrin system, while interactions with amino acids localized in proximity of heme could modulate the biological activity of diverse antifungal agents. In conclusion, HYPO1 conveys important information in an intuitive manner and can provide predictive capability for evaluating new compounds.