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Pyrazolo[3,4-d]pyrimidine derivatives 1–5, active as c-Src inhibitors, have been selected to be formulated as drug-loaded human serum albumin (HSA) nanoparticles, with the aim of improving their solubility and pharmacokinetic properties. The present study includes the optimization of a desolvation method-based procedure for preparing HSA nanoparticles. First, characterization by HPLC-MS and Dynamic Light Scattering (DLS) showed a good entrapment efficacy, a controllable particle size (between 100 and 200 nm) and an optimal stability over time, confirmed by an in vitro drug release assay. Then, 1–4 and the corresponding NPs were tested for their antiproliferative activity against neuroblastoma SH-SY5Y cell line. Notably, 3-NPs and 4-NPs were identified as the most promising formulation showing a profitable balance of stability, small size and a similar activity compared to the free drugs in cell-based assays. In addition, albumin formulations increase the solubility of pyrazolo[3,4-d]pyrimidine avoiding the use of DMSO as solubilizing agent.

En este trabajo se analiza las transformaciones que experimentó la educación superior argentina a partir de la profundización y consolidación del modelo de acumulación aperturista -o de valorización financiera- desde principios de la década '90., Fil: Pérez, Pedro Enrique. Universidad Nacional de Mar del Plata. Facultad de Ciencias Económicas y Sociales; Argentina., Fil: Hammond, Fernando. Universidad Nacional de Mar del Plata. Facultad de Ciencias Económicas y Sociales; Argentina., Fil: Schiavón, Guido Ezequiel. Universidad Nacional de Mar del Plata. Facultad de Ciencias Económicas y Sociales; Argentina., Fil: Fallacara Viñas, Mariano H. Universidad Nacional de Mar del Plata. Facultad de Ciencias Económicas y Sociales; Argentina.

In the last few years, several pyrrolo-pyrimidine derivatives have been either approved by the US FDA and in other countries for the treatment of different diseases or are currently in phase I/II clinical trials. Herein we present the synthesis and the characterization of a novel series of pyrrolo[2,3-d]pyrimidines, compounds 8a-j, and their activity against Glioblastoma multiforme (GBM). Docking studies and MM-GBSA analysis revealed the ability of such compounds to efficiently interact with the ATP binding site of Src. Enzymatic assays against a mini-panel of kinases (Src, Fyn, EGFR, Kit, Flt3, Abl, AblT315I) have been performed, showing an unexpected selectivity of our pyrrolo[2,3-d]pyrimidines for Src. Finally, the derivatives were tested for their antiproliferative potency on U87 GBM cell line. Compound 8h showed a considerable cytotoxicity effect against U87 cell line with an IC50 value of 7.1 μM.

The phosphorylation of tau protein is finely regulated by a balance between phosphorylation and dephosphorylation processes carried out by kinases and phosphatases. It has been suggested that the disruption of this equilibrium and consequent abnormal tau phosphorylation contribute to the aggregation of tau. The understanding of this important mechanism is of high interest because of the implication of tau aggregates in the development of Alzheimer’s disease (AD). In the last few years, among the possible strategies which could be used to reduce tau phosphorylation, the inhibition of certain tyrosine kinases has been suggested as a promising alternative to the common therapeutic approaches. In this chapter we will first give an overview of the tau protein kinases, their roles in cells, regulation and importance in AD. This will be followed by a more detailed description of the role of Fyn, a member of the Src family kinases, in the physiological development of CNS and the pathological progress of AD. How the inhibition of Fyn could be used as a new strategy in the fight against AD will be discussed.

Background: The National Toxicology Program (NTP) performed short-term toxicity studies of tetra- and pentavalent vanadium compounds, vanadyl sulfate and sodium metavanadate, respectively. Due to widespread human exposure and a lack of chronic toxicity data, there is concern for human health following oral exposure to soluble vanadium compounds. Objectives: To compare the potency and toxicological profile of vanadyl sulfate and sodium metavanadate using a short-term in vivo toxicity assay. Methods: Adult male and female Harlan Sprague Dawley (HSD) rats and B6C3F1/N mice, 5 per group, were exposed to vanadyl sulfate or sodium metavanadate, via drinking water, at concentrations of 0, 125, 250, 500, 1000 or 2000 mg/L for 14 days. Water consumption, body weights and clinical observations were recorded throughout the study; organ weights were collected at study termination. Results: Lower water consumption, up to −80% at 2000 mg/L, was observed at most exposure concentrations for animals exposed to either vanadyl sulfate or sodium metavanadate and was accompanied by decreased body weights at the highest concentrations for both compounds. Animals in the 1000 and 2000 mg/L sodium metavanadate groups were removed early due to overt toxicity. Thinness was observed in high-dose animals exposed to either compound, while lethargy and abnormal gait were only observed in vanadate-exposed animals. Conclusions: Based on clinical observations and overt toxicity, sodium metavanadate appears to be more toxic than vanadyl sulfate. Differential toxicity cannot be explained by differences in total vanadium intake, based on water consumption, and may be due to differences in disposition or mechanism of toxicity. Keywords: Pentavalent vanadium, Tetravalent vanadium, Vanadyl sulfate, Sodium metavanadate, B6C3F1/N, Harlan Sprague-Dawley, Short-term toxicity, National Toxicology Program

Since the mechanism of allosteric regulation was postulated for the first time in 1965 by Monod, Wyman and Changeux, 50 years have passed. From that moment our vision and understanding of the ligand–protein interaction process have been completely changed. Proteins started to be considered to be not fixed biological entities but flexible structures endowed with an activity which could be finely tuned by interaction with other proteins or new small molecules able to bind pockets different from the catalytic sites. In this chapter an in-depth description of one of the most studied allosteric modulation mechanisms will be provided. Abelson murine-leukemia viral-oncogene homolog-1 (c-Abl) protein kinase represents a noteworthy example of how a small post-translational modification (myristoylation of the N-terminal region of the protein sequence) can drive a mechanism of complex domain rearrangements, determining the activation state of the enzyme. Many efforts have been devoted, by scientists all around the world, to studying the molecular basis for the autoinhibition mechanism of c-Abl, and its derived oncogenic fusion protein breakpoint cluster region–Abl (Bcr–Abl), leading to the identification of the first allosteric inhibitor GNF-5, currently undergoing a Phase I clinical trial for the treatment of chronic myelogenous leukemia (CML).

The pyrrolo[2,3-d]pyrimidine nucleus is a deaza-isostere of adenine, the nitrogenous base of ATP, and is present in many ATP-competitive inhibitors of different kinases. In the last few years the number of articles and patents that have appeared involving this type of inhibitors has dramatically increased and some compounds have been approved for the treatment of inflammatory or myeloproliferative diseases. Other derivatives are currently being evaluated in clinical trials. This review deals with pyrrolo[2,3- d]pyrimidine derivatives active as kinase inhibitors that have been reported in the literature from 2011 to 2016, with a particular interest on the recently patented compounds. The molecules are classified depending on the inhibited kinase, focusing on their chemical structures.

The aim of this study was the preclinical development of a set of pyrazolo[3,4-d]pyrimidine structure-based small molecules ATP-competitive SRC inhibitors for the therapy of glioblastoma (GBM), a rare but extremely aggressive and infiltrative glial tumor with a very limited response to therapies. Ongoing preclinical and clinical studies of tyrosine kinase inhibitors (TKIs) for the therapy of GBM identified SRC family inhibitors as a significant and effective therapeutic strategy (i.e. dasatinib, bosutinib, PP2). In vitro Screening: From the wide in-house synthesized pyrazolo[3,4-d]pyrimidines’ library, nine compounds have been selected to be formulated and tested in in vitro and in vivo GBM pharmacological models. Among all the examined formulations, the prodrug approach has been applied to the candidate drugs, introducing the N-methylpiperazine moiety by a carbamate-based linker (in vivo enzymatically hydrolysable). Drugs and corresponding prodrugs have been screened on the basis of their SRC Ki and in vitro ADME properties. GBM U87 cell assays showed IC50 in the sub-micromolar range (1.5 - 15.0 µM) for almost all compounds and improved cellular uptake of the prodrugs in respect to the corresponding drugs. PK and Toxicity: After that, the most promising compound has been selected for further in vitro assays and in vivo tests. In vivo pharmacokinetics and pharmacodynamics have been evaluated for the compound by various formulations, routes of administration and dosages. In all cases investigated, the compound has been proved to reach the brain. As expected, prodrug plasmatic MRT and AUC confirmed the realization of an extended release formulation that allows a higher overall exposure to the drug. In addition, considering an estimated oral bioavailability of 40.4% and a 11-fold higher Cmax in respect to i.v. and i.p. administration, the oral route can be identified as the most advantageous for the compound for GBM treatment. Moreover, an acute toxicity study revealed that the LD50 for i.v. toxicity is more than 100 mg/kg with a good tolerability. In vivo Efficacy Tests: The selected compound and its prodrug were orally administered in GBM orthotopic mouse model and results indicated a median survival rate 10% greater for prodrug-treated mice in respect to drug-treated mice and 35% greater in respect to control group. The combination effect of the compound and radiotherapy was also investigated in subcutaneous U87 xenografted mice model and resulted in a reduction of the tumor growth close to 80% in respect to the control growth. Conclusions: Taking into account all the data collected regarding their pharmacological properties, pyrazolo[3,4-d]pyrimidines SRC inhibitors class of compounds deserve further investigation to show its potential to become a new therapy for GBM. Citation Format: Arianna Mancini, Anna Lucia Fallacara, Claudio Zamperini, Giulia Iovenitti, Alessio Molinari, Enrico Rango, Adriano Angelucci, Silvia Schenone, Maurizio Botta. Preclinical development of novel pyrazolo[3,4-d]pyrimidines structure-based TKIs for the treatment of glioblastoma [abstract]. In: Proceedings of the American Association for Cancer Research Annual Meeting 2019; 2019 Mar 29-Apr 3; Atlanta, GA. Philadelphia (PA): AACR; Cancer Res 2019;79(13 Suppl):Abstract nr 2201.

Purpose Glioblastoma multiforme (GBM) is the most aggressive types of central nervous system tumors. The aim of the project is to validate an innovative molecule developed by Lead Discovery Siena [LDS] showing inhibitory activity against Src kinases to be associated with proton therapy treatments. Materials Human glioblastoma cells (U87) were treated at INFN-LNS in Catania with 2 and 10 Gy of proton beams at dose rate of 10 Gy/min in the middle of the extended modulated Bragg peak and in combination with different concentrations of the LDS molecule (10 and 20 μM). The fraction of surviving cells (SF) was evaluated with the clonogenicity test 15 days after irradiation. Results The data in the figure show the synergistic effect of the combined treatment with LDS. Conclusions In vitro studies confirmed the efficacy of the hadron therapy treatment in combination with the molecule. The next step is to translate these studies on the mouse model thanks to the existence of an Animal Facility created by the synergy between the following institution: the LNS-INFN, the University of Catania – Capir Center, IBFM-CNR and H. Cannizzaro, with the departments of Nuclear Medicine and Medical Physics. The facility will be able to provide unique research activities in the European panorama: hadron therapy treatments, dose distribution studies using the Monte Carlo GEANT4 method, molecular imaging using microPET/ CT tomography with different radiotracers and image processing implementation for therapy response quantification.

Besides the unquestionable positive effects of solar exposure for human health, UV rays have been widely investigated for toxicology aspects related to excessive UVB and UVA doses, which involve sunburns, skin aging, DNA skin damage and tumorigenesis. At present, synthetic and mineral sunscreens are used to protect against these damages but several natural molecules can provide UV protection, including also synergic effect or enhanced photo stability. Although a large number of herbal extracts and plant origin molecules can deserve potential applications, most of the study reported utilizes different method and different strategies of investigation, making thus difficult to understand the real versus claimed potential. This is possibly one of the reasons why, beside the large body of literature there are no officially approved natural commercial sun-filter but a consistent number of commercially available solar products (sunscreen) on the market that contain herbal derivatives. In this review we have evaluated the papers appeared in the last 15years and we have critically collected the most significant data. Several databases, namely Scifinder, Pubmed, Google Scholar, ISI-Web of Science and Scopus, were used as literature sources; excluding patents and symposium or congress papers. Only articles in the English language have been selected. New formulation, new skin delivery systems, skin penetration enhancers and boosters are most likely the next frontier of investigation in order to better understand the role of whole herbal extracts in exerting their photo protective activity.

The goal of this project is to conduct the first geographically distributed, low-frequency skywave propagation measurements during a solar eclipse. There is a lack of knowledge about how radio waves below frequencies of 500 kHz are affected by a total eclipse and a lack of experimental data reflecting these low-frequency radio wave transmissions at geographically diverse locations during an eclipse. A low-frequency band receiver system for people across the United States to assemble and use is designed, allowing for a crowd-sourced collection of measurements of relative signal strength of the WWVB and Dixon low-frequency station signals during the eclipse over North America on August 21, 2017.

The major clinical challenge in drug-resistant chronic myelogenous leukemia (CML) is currently represented by the Bcr-Abl T315I mutant, which is unresponsive to treatment with common first and second generation ATP-competitive tyrosine kinase inhibitors (TKIs). Allosteric inhibition of Bcr-Abl represent a new frontier in the fight against resistant leukemia and few candidates have been identified in the last few years. Among these, myristate pocket (MP) binders discovered by Novartis (e.g. GNF2/5) showed promising results, although they proved to be active against the T315I mutant only in combination with first and second generation ATP-competitive inhibitors. Here we used a cascade screening approach based on sequential fluorescence polarization (FP) screening, in silico docking/dynamics studies and kinetic-enzymatic studies to identify novel MP binders. A pyrazolo[3,4-d]pyrimidine derivative (6) has been identified as a promising allosteric inhibitor active on 32D leukemia cell lines (expressing Bcr-Abl WT and T315I) with no need of combination with any ATP-competitive inhibitor.

Influenza is an infectious disease that represents an important public health burden, with high impact on the global morbidity, mortality, and economy. The poor protection and the need of annual updating of the anti-influenza vaccine, added to the rapid emergence of viral strains resistant to current therapy make the need for antiviral drugs with novel mechanisms of action compelling. In this regard, the viral RNA polymerase is an attractive target that allows the design of selective compounds with reduced risk of resistance. In previous studies we showed that the inhibition of the polymerase acidic protein-basic protein 1 (PA-PB1) interaction is a promising strategy for the development of anti-influenza agents. Starting from the previously identified 3-cyano-4,6-diphenyl-pyridines, we chemically modified this scaffold and explored its structure-activity relationships. Noncytotoxic compounds with both the ability of disrupting the PA-PB1 interaction and antiviral activity were identified, and their mechanism of target binding was clarified with molecular modeling simulations.

Influenza is an infectious disease that represents an important public health burden, with high impact on the global morbidity, mortality, and economy. The poor protection and the need of annual updating of the anti-influenza vaccine, added to the rapid emergence of viral strains resistant to current therapy make the need for antiviral drugs with novel mechanisms of action compelling. In this regard, the viral RNA polymerase is an attractive target that allows the design of selective compounds with reduced risk of resistance. In previous studies we showed that the inhibition of the polymerase acidic protein-basic protein 1 (PA-PB1) interaction is a promising strategy for the development of anti-influenza agents. Starting from the previously identified 3-cyano-4,6-diphenyl-pyridines, we chemically modified this scaffold and explored its structure-activity relationships. Noncytotoxic compounds with both the ability of disrupting the PA-PB1 interaction and antiviral activity were identified, and their mechanism of target binding was clarified with molecular modeling simulations.

This contribution tries to reintroduce Stereotomy within the field of “research by design”: the discipline, in fact, can be used as a means of re-composition of the design, project and execution phases. Starting from the origin of this break-up, the focus moves to the actual value of geometric and formal prefiguration and to the validity criteria that make its re-introduction desirable, both as educational discipline and design tool. In addition, it's suggested a line of research related to its critical update and the methods through which figure out the possible outcomes of its application. Particular attention is given to the prototype: only the material realization allows to obtain a tangible result to creative speculation. In the last part 7 stone prototypes will be presented. They have been developed during recent years as a result of the attempt to combine multiple instances into a synthetic architectural object.

En este trabajo se intenta comprender la situación de los estudiantes que abandonan sus estudios universitarios en la UNMDP, en el transcurso de los primeros cuatrimestres, atendiendo especialmente su vinculación con los contenidos y modalidades de implementación de la currícula universitaria. Dentro de la multiplicidad de factores que configuran la problemática del abandono, seleccionamos a los efectos analíticos, aquellos vinculados a los contenidos temáticos, sus modalidades de implementación, es decir aquellos que denominaremos "dispositivos pedagógicos" referidos concretamente a la currícula de las distintas carreras que se dictan en la UNMDP. En este sentido nos preguntamos: ¿Qué prácticas organizacionales se constituyen como barreras de entrada a la universidad dificultando la permanencia de los estudiantes en los primeros años?, dado que resulta evidente la preocupación actual de la Universidad por abordar la compleja problemática del abandono de los estudios universitarios. Concordantemente con ello, intentaremos establecer las dimensiones que permitan la comprensión del fenómeno enunciado y den sustento a la toma de decisiones a través del reconocimiento, explicitación y puesta en práctica de las cuestiones que intervienen en el abandono de los estudios., Fil: González Carella, María Inés. Universidad Nacional de Mar del Plata. Facultad de Ciencias Económicas y Sociales; Argentina., Fil: Fallacara Viñas, Mariano H. Universidad Nacional de Mar del Plata. Facultad de Ciencias Económicas y Sociales; Argentina., Fil: Schiavón, Guido Ezequiel. Universidad Nacional de Mar del Plata. Facultad de Ciencias Económicas y Sociales; Argentina.

The vault of the Arles City Hall, or Hotel de Ville, represents the architect’s revenge on the corporations of masons. Completed in 1676, the relationship of span to rise of the vault make it the boldest work of masonry in Europe, and while this complex vault appears to be a unitary structure, two vaults actually share the work, leaning against each other on the big arch. Bibliographic and archival research showed that surveys of the vault were missing; the only ancient survey was lost in the 1970s. A recent survey campaign made an analysis possible, leading to a hypothesis about the architect Mansart’s choices, based on hypothetical solutions to resolve the formal construction issues of the vault. A connoisseur of geometry and optics, Mansart knew that the human eye was unable to perceive the exact geometry of a surface. Knowing that he couldn’t control the intersections of vault portions and then the joints of the rows in the space, he introduced a solution that involved drawing the intersections in plan and then projecting them on the vault to obtain the spatial intersections. No further constructions of the bold type followed the vaulted space in the Hotel de ville, because the spatial research that linked the new discipline (stereotomy) to the quality of architectural space had by then come to an end. La voute de l’Hotel de ville d’Arles est le chef d’oeuvre de la stereotomie francaise [Perouse de Montclos 1983: 123-126]

This study evaluated the effects of dietary methylmercury (MeHg) on immune system development in captive-reared nestling American kestrels (Falco sparverius) to determine whether T cell-mediated and antibody-mediated adaptive immunity are targets for MeHg toxicity at environmentally relevant concentrations. Nestlings received various diets, including 0 (control), 0.6, and 3.9 µg/g (dry wt) MeHg for up to 18 d posthatch. Immunotoxicity endpoints included cell-mediated immunity (CMI) using the phytohemagglutinin (PHA) skin-swelling assay and antibody-mediated immune response via the sheep red blood cell (SRBC) hemagglutination assay. T cell- and B cell-dependent histological parameters in the spleen, thymus, and bursa of Fabricius were correlated with the functional assays. For nestlings in the 0.6 and 3.9 µg/g MeHg groups, CMI was suppressed by 73 and 62%, respectively, at 11 d of age. Results of this functional assay were correlated with T cell-dependent components of the spleen and thymus. Dose-dependent lymphoid depletion in spleen tissue directly affected the proliferation of T-lymphocyte populations, insofar as lower stimulation indexes from the PHA assay occurred in nestlings with lower proportions of splenic white pulp and higher THg concentrations. Nestlings in the 3.9 µg/g group also exhibited lymphoid depletion and a lack of macrophage activity in the thymus. Methylmercury did not have a noticeable effect on antibody-mediated immune function or B cell-dependent histological correlates. We conclude that T cell-mediated immunosuppression is the primary target of MeHg toward adaptive immunity in developing kestrels. This study provides evidence that environmentally relevant concentrations of MeHg may compromise immunocompetence in a developing terrestrial predator and raises concern regarding the long-term health effects of kestrels that were exposed to dietary MeHg during early avian development.

A high-throughput molecular docking approach was successfully applied for the selection of potential inhibitors of the Influenza RNA-polymerase which act by targeting the PA-PB1 protein-protein interaction. Commercially available compounds were purchased and biologically evaluated in vitro using an ELISA-based assay. As a result, some compounds possessing a 3-cyano-4,6-diphenyl-pyridine nucleus emerged as effective inhibitors with the best ones showing IC50 values in the micromolar range.

Dry eye syndrome is a common disease which can damage the corneal epithelium. It is treated with eye drops to stimulate tear production and hydrate the corneal surface. The most prescribed artificial tear remedies contain hyaluronic acid (HA), which enhances epithelial wound healing, improving tissue health. To the best of our knowledge, only a few recent studies have investigated cross-linked HA (HA-CL) in eye drops for human applications. This work consists in an in vitro evaluation of the re-epithelialization ability of two different preparations containing a recently synthetized HA cross-linked with urea: 0.02% (w/v) HA-CL (solution 1, S1), and 0.4% (w/v) HA-CL (solution 2, S2). The study was conducted on both 2D human corneal cells (HCEpiC) and 3D reconstructed tissues of human corneal epithelium (HCE). Viability by 3(4,5-dimethylthiazol-2)2,5-diphenyltetrazolium bromide (MTT) test, pro-inflammatory cytokine release (interleukin-8, IL-8) by ELISA, and morphology by hematoxylin and eosin (HE) staining were evaluated. In addition, to understand the molecular basis of the re-epithelialization properties, cyclin D1 levels were assessed by western blot. The results showed no cellular toxicity, a slight decrease in IL-8 release, and restoration of epithelium integrity when the wounded 3D model was treated with S1 and S2. In parallel, cyclin D1 levels increased in cells treated with both S1 and S2.

In this study, the isolation of 52 mycobactin-independent fast growing mycobacteria from 631 bulk milk samples (8.2%), is reported. These strains, isolated during a bulk milk survey for Mycobacterium avium subsp. paratuberculosis (Map), strongly affected Map detection both by PCR and by culture, as they gave a positive IS900 PCR signal and resulted to totally inhibit the growth of Map when spotted on HEYM slants already inoculated with 200 μl of 10-fold dilutions containing from 5 × 10 to 5 × 103 Map cells/ml. 16S rRNA gene sequencing, using the MicroSeq 500 16S rDNA Bacterial Sequencing Kit (Applied Biosystems), was performed on a subset of six strains, identifying Mycobacterium porcinum with 100% homology in all six cases. The 52 strains were characterized by PCR-restriction fragment length polymorphism (RFLP) analysis of the hsp65 gene, which confirmed the identification of M. porcinum for all the isolates. Using specific primers designed on the Map-IS900 sequence and on the M. porcinum sequence determined in this study, a 1385 bp sequence from the M. porcinum genome was characterized. This IS900-like sequence showed 82% homology with Map IS900. From our findings the following results emerged: (a) any culture showing one or more M. porcinum colonies represents a potential “false negative” result and should therefore be considered as contaminated; (b) IS900-like elements could be more widespread than was previously thought; (c) IS900 PCR positive results should be interpreted cautiously, as confirmed by the evidence that the primer pair used in this study resulted not to be specific.

This paper examines the changes from 1955 to 2002 in soil erosion and deposition due to changes in land-use patterns in the semi-arid territory of Craco, which is characterized by landsliding and badland erosion. The area underwent continuous degradation during the last century due not only to its lithological vulnerability but also to the anthropic pressure favoured by the introduction of Common Agricultural Policy (CAP) measures, which has led to the reclamation of scrub lands and badlands for durum wheat cultivation. Our analysis integrates the Unit Stream Power Erosion Deposition (USPED) model with a geographic information system (GIS) to quantify erosion risk and predict deposition patterns. Soil data, land use inventory, digital elevation data and climatic atlases were used as resource data sets to generate USPED factor values. The obtained results correlate well with field measured erosion data by other researchers. In the investigated 47 years, stable areas decreased by about 280 ha (3·8% of the total surface area), largely attributable to the increase of the low and moderate erosion intensity without significant change in sedimentation. Results from this study have implications related to understanding the geomorphic response of sites that were abandoned following remodelling due to the application of the F measure of Regulation CEE 2078/92. The average annual erosion rates estimated for abandoned and remodelled sites are respectively 15·99 and 10·64 t ha−1, meaning that the total amount of erosion in 20 years could be estimated at around 100 t ha−1. Copyright © 2007 John Wiley & Sons, Ltd.