55 research outputs found

    ReSS: A tool for discovering relevant sets in complex systems

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    Abstract A complex system can be composed of inherent dynamical structures, i.e., relevant subsets of variables interacting tightly with one another and loosely with other subsets. In the literature, some effective methods to identify such relevant sets rely on the so-called Relevance Indexes (RIs), measuring subset relevance based on information theory principles. In this paper, we present ReSS, a collection of CUDA-based programs computing two of such RIs, either through an exhaustive search or a niching metaheuristic when the system dimension is too large. ReSS also includes a script that iteratively activates the search and identifies hierarchical relationships among the relevant subsets. The main purpose of ReSS is to establish a common and easy-to-use general RI-based platform for the analysis of complex systems and other possible applications

    Synthesis of divalent ligands of beta-thio- and beta-N-galactopyranosides and related lactosides and their evaluation as substrates and inhibitors of Trypanosoma cruzi trans-sialidase

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    In this work we describe the synthesis of mono- and divalent β-N- and β-S-galactopyranosides and related lactosides built on sugar scaffolds and their evaluation as substrates and inhibitors of the Trypanosoma cruzi trans-sialidase (TcTS). This enzyme catalyzes the transfer of sialic acid from an oligosaccharidic donor in the host, to parasite βGalp terminal units and it has been demonstrated that it plays an important role in the infection. Herein, the enzyme was also tested as a tool for the chemoenzymatic synthesis of sialic acid containing glycoclusters. The transfer reaction of sialic acid was performed using a recombinant TcTS and 3?-sialyllactose as sialic acid donor, in the presence of the acceptor having βGalp non reducing ends. The products were analyzed by high performance anion exchange chromatography with pulse amperometric detection (HPAEC-PAD). The ability of the different S-linked and N-linked glycosides to inhibit the sialic acid transfer reaction from 3?-sialyllactose to the natural substrate N-acetyllactosamine, was also studied. Most of the substrates behaved as good acceptors and moderate competitive inhibitors. A di-N-lactoside showed to be the strongest competitive inhibitor among the compounds tested (70% inhibition at equimolar concentration). The usefulness of the enzymatic trans-sialylation for the preparation of sialylated ligands was assessed by performing a preparative sialylation of a divalent substrate, which afforded the monosialylated compound as main product, together with the disialylated glycocluster.Fil: Cano, María Emilia. Consejo Nacional de Investigaciones Científicas y Técnicas. Oficina de Coordinación Administrativa Ciudad Universitaria. Centro de Investigaciones En Hidratos de Carbono; ArgentinaFil: Agusti, Rosalia. Consejo Nacional de Investigaciones Científicas y Técnicas. Oficina de Coordinación Administrativa Ciudad Universitaria. Centro de Investigaciones En Hidratos de Carbono; ArgentinaFil: Cagnoni, Alejandro. Consejo Nacional de Investigaciones Científicas y Técnicas. Oficina de Coordinación Administrativa Ciudad Universitaria. Centro de Investigaciones En Hidratos de Carbono; ArgentinaFil: Tesoriero, María Florencia. Consejo Nacional de Investigaciones Científicas y Técnicas. Oficina de Coordinación Administrativa Ciudad Universitaria. Centro de Investigaciones En Hidratos de Carbono; ArgentinaFil: Kovenski, José. Université de Picardie Jules Verne; FranciaFil: Uhrig, Maria Laura. Consejo Nacional de Investigaciones Científicas y Técnicas. Oficina de Coordinación Administrativa Ciudad Universitaria. Centro de Investigaciones En Hidratos de Carbono; ArgentinaFil: Muchnik, Rosa. Consejo Nacional de Investigaciones Científicas y Técnicas. Oficina de Coordinación Administrativa Ciudad Universitaria. Centro de Investigaciones En Hidratos de Carbono; Argentin

    A relevance index method to infer global properties of biological networks

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    Many complex systems, both natural and artificial, may be represented by networks of interacting nodes. Nevertheless, it is often difficult to find meaningful correspondences between the dynamics expressed by these systems and the topological description of their networks. In contrast, many of these systems may be well described in terms of coordinated behavior of their dynamically relevant parts. In this paper we use the recently proposed Relevance Index approach, based on information-theoretic measures. Starting from the observation of the dynamical states of any system, the Relevance Index is able to provide information about its organization. Moreover, we show how the application of the proposed approach leads to novel and effective interpretations in the T helper network case study

    Does the addition of a second daily session of hyperbaric oxygen therapy to intratympanic steroid influence the outcomes of sudden hearing loss? [L’aggiunta di una seconda sessione giornaliera di camera iperbarica al trattamento steroideo intratimpanico influenza i risultati terapeutici nella sordità improvvisa?]

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    The aim of this study is to investigate whether, in addition to intratympanic steroid therapy, additional hyperbaric oxygen therapy (HBOT) sessions per day (twice a day for 5 days) is more useful than one session per day for 10 days in patients affected by severe and profound idiopathic sudden sensorineural hearing loss (ISSNHL). A total of 55 patients affected by unilateral severe and profound ISSNHL were recruited. Two protocols were adopted. In the first, 27 patients (13 with profound and 14 with severe hearing loss) underwent one session of HBOT per day for 10 days, 6 days a week. An HBOT session comprised a period of 14 minutes air compression followed by 90 min at 2.4 atm absolute (ATA) followed by a decompression period of 15 min in oxygen. Patients breathed 100% oxygen through an appropriate mask checked for leaks. Patients were given 0.4 ml of 62.5 mg/ml of intratympanic prednisolone during the first three days of the protocol. In the second protocol, 28 patients (10 with profound and 18 with severe hearing loss) received 10 sessions of HBOT, twice a day for five days, 2.4 ATA 90 min 100% oxygen. The intratympanic injections of prednisolone were given between the two sessions of HBOT during the first three days of the protocol. Since there were no significant differences in hearing outcomes between the two protocols, the present study shows that the protocol of two sessions of HBOT per day is a valid treatment and equally effective as the one HBOT session per day, but with shorter treatment time

    Galectin-1 fosters an immunosuppressive microenvironment in colorectal cancer by reprogramming CD8+ regulatory T cells

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    Colorectal cancer (CRC) represents the third most common malignancy and the second leading cause of cancer-related deaths worldwide. Although immunotherapy has taken center stage in mainstream oncology, it has shown limited clinical efficacy in CRC, generating an urgent need for discovery of new biomarkers and potential therapeutic targets. Galectin-1 (Gal-1), an endogenous glycan-binding protein, induces tolerogenic programs and contributes to tumor cell evasion of immune responses. Here, we investigated the relevance of Gal-1 in CRC and explored its modulatory activity within the CD8+ regulatory T cell (Treg) compartment. Mice lacking Gal-1 (Lgals1−/−) developed a lower number of tumors and showed a decreased frequency of a particular population of CD8+CD122+PD-1+ Tregs in the azoxymethane-dextran sodium sulfate model of colitis-associated CRC. Moreover, silencing of tumor-derived Gal-1 in the syngeneic CT26 CRC model resulted in reduced number and attenuated immunosuppressive capacity of CD8+CD122+PD-1+ Tregs, leading to slower tumor growth. Moreover, stromal Gal-1 also influenced the fitness of CD8+ Tregs, highlighting the contribution of both tumor and stromal-derived Gal-1 to this immunoregulatory effect. Finally, bioinformatic analysis of a colorectal adenocarcinoma from The Cancer Genome Atlas dataset revealed a particular signature characterized by high CD8+ Treg score and elevated Gal-1 expression, which delineates poor prognosis in human CRC. Our findings identify CD8+CD122+PD-1+ Tregs as a target of the immunoregulatory activity of Gal-1, suggesting a potential immunotherapeutic strategy for the treatment of CRC.Fil: Cagnoni, Alejandro. Consejo Nacional de Investigaciones Científicas y Técnicas. Instituto de Biología y Medicina Experimental. Fundación de Instituto de Biología y Medicina Experimental. Instituto de Biología y Medicina Experimental; ArgentinaFil: Giribaldi, María Laura. Consejo Nacional de Investigaciones Científicas y Técnicas. Instituto de Biología y Medicina Experimental. Fundación de Instituto de Biología y Medicina Experimental. Instituto de Biología y Medicina Experimental; ArgentinaFil: Blidner, Ada Gabriela. Consejo Nacional de Investigaciones Científicas y Técnicas. Instituto de Biología y Medicina Experimental. Fundación de Instituto de Biología y Medicina Experimental. Instituto de Biología y Medicina Experimental; ArgentinaFil: Cutine, Anabela María. Consejo Nacional de Investigaciones Científicas y Técnicas. Instituto de Biología y Medicina Experimental. Fundación de Instituto de Biología y Medicina Experimental. Instituto de Biología y Medicina Experimental; ArgentinaFil: Gatto, Sabrina Gisela. Consejo Nacional de Investigaciones Científicas y Técnicas. Instituto de Biología y Medicina Experimental. Fundación de Instituto de Biología y Medicina Experimental. Instituto de Biología y Medicina Experimental; ArgentinaFil: Morales, Rosa María. Consejo Nacional de Investigaciones Científicas y Técnicas. Instituto de Biología y Medicina Experimental. Fundación de Instituto de Biología y Medicina Experimental. Instituto de Biología y Medicina Experimental; ArgentinaFil: Salatino, Mariana. Consejo Nacional de Investigaciones Científicas y Técnicas. Instituto de Biología y Medicina Experimental. Fundación de Instituto de Biología y Medicina Experimental. Instituto de Biología y Medicina Experimental; ArgentinaFil: Abba, Martín Carlos. Universidad Nacional de La Plata. Facultad de Ciencias Médicas. Centro de Investigaciones Inmunológicas Básicas y Aplicadas; ArgentinaFil: Croci Russo, Diego Omar. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Mendoza. Instituto de Histología y Embriología de Mendoza Dr. Mario H. Burgos. Universidad Nacional de Cuyo. Facultad de Ciencias Médicas. Instituto de Histología y Embriología de Mendoza Dr. Mario H. Burgos; ArgentinaFil: Mariño, Karina Valeria. Consejo Nacional de Investigaciones Científicas y Técnicas. Instituto de Biología y Medicina Experimental. Fundación de Instituto de Biología y Medicina Experimental. Instituto de Biología y Medicina Experimental; ArgentinaFil: Rabinovich, Gabriel Adrián. Consejo Nacional de Investigaciones Científicas y Técnicas. Instituto de Biología y Medicina Experimental. Fundación de Instituto de Biología y Medicina Experimental. Instituto de Biología y Medicina Experimental; Argentina. Universidad de Buenos Aires. Facultad de Ciencias Exactas y Naturales; Argentin

    Escherichia coli β-Galactosidase Inhibitors through Modifications at the Aglyconic Moiety: Experimental Evidence of Conformational Distortion in the Molecular Recognition Process

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    Herein, we describe the use of thioglycosides as glycosidase inhibitors by employing novel modifications at the reducing end of these glycomimetics. The inhibitors display a basic galactopyranosyl unit (1-4)-bonded to a 3-deoxy-4-thiopentopyranose moiety. The molecular basis of the observed inhibition has been studied by using a combination of NMR spectroscopy and molecular modeling techniques. It is demonstrated that these molecules are not recognized by Escherichia coli bgalactosidase in their ground-state conformation, with a conformational selection process taking place. In fact, the observed conformational distortion depends on the chemical nature of the compounds and results from the rotation around the glycosidic linkage (variation of F or Y) or from the deformation of the six-membered ring of the pentopyranose. The bound conformations of the ligand are adapted in the enzymatic pocket with a variety of hydrogen-bond, van der Waals, and stacking interactions.Fil: Calle, Luis. Consejo Superior de Investigaciones Cientificas. Centro de Investigaciones Biologicas; España;Fil: Roldós, Virginia. Consejo Superior de Investigaciones Cientificas. Centro de Investigaciones Biologicas; España;Fil: Cañada, Javier F.. Consejo Superior de Investigaciones Cientificas. Centro de Investigaciones Biologicas; España;Fil: Uhrig, Maria Laura. Consejo Nacional de Investigaciones Científicas y Técnicas. Oficina de Coordinación Administrativa Ciudad Universitaria. Centro de Investigaciones en Hidratos de Carbono; Argentina;Fil: Cagnoni, Alejandro. Consejo Nacional de Investigaciones Científicas y Técnicas. Oficina de Coordinación Administrativa Ciudad Universitaria. Centro de Investigaciones en Hidratos de Carbono; Argentina;Fil: Manzano, Veronica Elena. Consejo Nacional de Investigaciones Científicas y Técnicas. Oficina de Coordinación Administrativa Ciudad Universitaria. Instituto de Química, Física de los Materiales, Medioambiente y Energía; Argentina; Consejo Nacional de Investigaciones Científicas y Técnicas. Oficina de Coordinación Administrativa Ciudad Universitaria. Centro de Investigaciones en Hidratos de Carbono; Argentina;Fil: Varela, Oscar Jose. Consejo Nacional de Investigaciones Científicas y Técnicas. Oficina de Coordinación Administrativa Ciudad Universitaria. Centro de Investigaciones en Hidratos de Carbono; Argentina;Fil: Jiménez Barbero, Jesús. Consejo Superior de Investigaciones Cientificas. Centro de Investigaciones Biologicas; España

    Glycosylation-dependent circuits synchronize the pro-angiogenic and immunoregulatory functions of myeloid-derived suppressor cells in cancer

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    Myeloid-derived suppressor cells (MDSCs) favor tumorprogression and therapy resistance by reprogramming antitumor immunity and promoting angiogenesis. To elucidatethe mechanisms that synchronize these functions, we investigated the role of glycosylation-dependent, galectin-1(Gal1)-driven circuits in coupling immunoregulatory andpro-angiogenic activities of MDSCs. Flow cytometry andHPLC-HILIC/WAX revealed an activation-dependent glycanprofile in monocytic and polymorphonuclear MDSCs (p=0.03)that controlled Gal1 binding and was more prominent in tumor microenvironments. Exposure to Gal1 led to concomitant activation of immunosuppression and angiogenesisprograms in bone marrow derived MDSCs. Flow cytometryof Gal1-conditioned MDSCs showed higher expression ofimmune checkpoint molecules, including programmed deathligand-1 (PD-L1) (p=0.005) and indoleamine 2,3-dioxygenase (IDO) (p=0.037) and greater production of reactive oxygen species (ROS) and nitric oxide (NO) (p=0.02). In vitro,Gal1-conditioned MDSCs showed greater T-cell suppressive capacity (p=0.03) and higher IL-10 (p=0.04) and IL-27(p=0.003) secretion. These effects were accompanied by enhanced endothelial cell migration, tube formation, 3D-sprouting and vascularization (p<0.05). In vivo, Gal1-conditionedMDSCs accelerated tumor growth (p=0.001) and fosteredimmune evasion and vascularization programs in Gal1-deficient colorectal tumors. Mechanistically, mass spectrometry,immunoblot and blocking assays identified the CD18/CD11b/CD177 complex as a bona fide Gal1 receptor and STAT3 asa key signaling pathway coupling these functions. Accordingly, a combined algorithm that integrates Gal1 expressionand MDSC phenotype, showed critical prognostic value bydelineating the immune landscape and clinical outcome ofhuman cancers. Thus, glycosylation-dependent Gal1-drivencircuits favor tumor progression by coupling immunoregulatory and pro-angiogenic programs of MDSCs via CD18- andSTAT3-dependent pathways.Fil: Blidner, Ada Gabriela. Consejo Nacional de Investigaciones Científicas y Técnicas. Instituto de Biología y Medicina Experimental. Fundación de Instituto de Biología y Medicina Experimental. Instituto de Biología y Medicina Experimental; ArgentinaFil: Bach, Camila Agustina. Consejo Nacional de Investigaciones Científicas y Técnicas. Instituto de Biología y Medicina Experimental. Fundación de Instituto de Biología y Medicina Experimental. Instituto de Biología y Medicina Experimental; ArgentinaFil: García, Pablo Alfredo. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Mendoza. Instituto de Histología y Embriología de Mendoza Dr. Mario H. Burgos. Universidad Nacional de Cuyo. Facultad de Ciencias Médicas. Instituto de Histología y Embriología de Mendoza Dr. Mario H. Burgos; ArgentinaFil: Cagnoni, Alejandro. Consejo Nacional de Investigaciones Científicas y Técnicas. Instituto de Biología y Medicina Experimental. Fundación de Instituto de Biología y Medicina Experimental. Instituto de Biología y Medicina Experimental; ArgentinaFil: Manselle Cocco, Montana Nicolle. Consejo Nacional de Investigaciones Científicas y Técnicas. Instituto de Biología y Medicina Experimental. Fundación de Instituto de Biología y Medicina Experimental. Instituto de Biología y Medicina Experimental; ArgentinaFil: Pinto, Nicolás Alejandro. Consejo Nacional de Investigaciones Científicas y Técnicas. Instituto de Biología y Medicina Experimental. Fundación de Instituto de Biología y Medicina Experimental. Instituto de Biología y Medicina Experimental; ArgentinaFil: Torres, Nicolás. Consejo Nacional de Investigaciones Científicas y Técnicas. Instituto de Biología y Medicina Experimental. Fundación de Instituto de Biología y Medicina Experimental. Instituto de Biología y Medicina Experimental; ArgentinaFil: Gatto, Sabrina Gisela. Consejo Nacional de Investigaciones Científicas y Técnicas. Instituto de Biología y Medicina Experimental. Fundación de Instituto de Biología y Medicina Experimental. Instituto de Biología y Medicina Experimental; ArgentinaFil: Sarrias, Luciana. Consejo Nacional de Investigaciones Científicas y Técnicas. Oficina de Coordinación Administrativa Houssay. Instituto de Química y Físico-Química Biológicas "Prof. Alejandro C. Paladini". Universidad de Buenos Aires. Facultad de Farmacia y Bioquímica. Instituto de Química y Físico-Química Biológicas; ArgentinaFil: Giribaldi, María Laura. Consejo Nacional de Investigaciones Científicas y Técnicas. Instituto de Biología y Medicina Experimental. Fundación de Instituto de Biología y Medicina Experimental. Instituto de Biología y Medicina Experimental; ArgentinaFil: Merlo, Joaquín Pedro. Consejo Nacional de Investigaciones Científicas y Técnicas. Instituto de Biología y Medicina Experimental. Fundación de Instituto de Biología y Medicina Experimental. Instituto de Biología y Medicina Experimental; ArgentinaFil: Pérez Sáez, Juan Manuel. Consejo Nacional de Investigaciones Científicas y Técnicas. Instituto de Biología y Medicina Experimental. Fundación de Instituto de Biología y Medicina Experimental. Instituto de Biología y Medicina Experimental; ArgentinaFil: Salatino, Mariana. Consejo Nacional de Investigaciones Científicas y Técnicas. Instituto de Biología y Medicina Experimental. Fundación de Instituto de Biología y Medicina Experimental. Instituto de Biología y Medicina Experimental; ArgentinaFil: Troncoso, María Fernanda. Consejo Nacional de Investigaciones Científicas y Técnicas. Oficina de Coordinación Administrativa Houssay. Instituto de Química y Físico-Química Biológicas "Prof. Alejandro C. Paladini". Universidad de Buenos Aires. Facultad de Farmacia y Bioquímica. Instituto de Química y Físico-Química Biológicas; ArgentinaFil: Mariño, Karina Valeria. Consejo Nacional de Investigaciones Científicas y Técnicas. Instituto de Biología y Medicina Experimental. Fundación de Instituto de Biología y Medicina Experimental. Instituto de Biología y Medicina Experimental; ArgentinaFil: Abba, Martín Carlos. Universidad Nacional de La Plata; Argentina. Consejo Nacional de Investigaciones Científicas y Técnicas; ArgentinaFil: Croci, Diego O.. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Mendoza. Instituto de Histología y Embriología de Mendoza Dr. Mario H. Burgos. Universidad Nacional de Cuyo. Facultad de Ciencias Médicas. Instituto de Histología y Embriología de Mendoza Dr. Mario H. Burgos; ArgentinaFil: Rabinovich, Gabriel Adrián. Consejo Nacional de Investigaciones Científicas y Técnicas. Instituto de Biología y Medicina Experimental. Fundación de Instituto de Biología y Medicina Experimental. Instituto de Biología y Medicina Experimental; ArgentinaLXVI Annual Meeting of Sociedad Argentina de Investigación Clínica; LXIX Annual Meeting of Sociedad Argentina de Inmunología; LIII Annual Meeting of Asociación Argentina de Farmacología Experimental and XI Annual Meeting of Asociación Argentina de NanomedicinasArgentinaSociedad Argentina de Investigación ClínicaSociedad Argentina de InmunologíaAsociación Argentina de Farmacología ExperimentalAsociación Argentina de Nanomedicin

    Galectin-1 fosters an immunosuppressive microenvironment in colorectal cancer by reprogramming CD8⁺ regulatory T cells

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    Colorectal cancer (CRC) represents the third most common malignancy and the second leading cause of cancer-related deaths worldwide. Although immunotherapy has taken center stage in mainstream oncology, it has shown limited clinical efficacy in CRC, generating an urgent need for discovery of new biomarkers and potential therapeutic targets. Galectin-1 (Gal-1), an endogenous glycan-binding protein, induces tolerogenic programs and contributes to tumor cell evasion of immune responses. Here, we investigated the relevance of Gal-1 in CRC and explored its modulatory activity within the CD8⁺ regulatory T cell (Treg) compartment. Mice lacking Gal-1 (Lgals1 -/- ) developed a lower number of tumors and showed a decreased frequency of a particular population of CD8⁺CD122⁺PD-1⁺ Tregs in the azoxymethane-dextran sodium sulfate model of colitis-associated CRC. Moreover, silencing of tumor-derived Gal-1 in the syngeneic CT26 CRC model resulted in reduced number and attenuated immunosuppressive capacity of CD8⁺CD122⁺PD-1⁺ Tregs, leading to slower tumor growth. Moreover, stromal Gal-1 also influenced the fitness of CD8⁺ Tregs, highlighting the contribution of both tumor and stromal-derived Gal-1 to this immunoregulatory effect. Finally, bioinformatic analysis of a colorectal adenocarcinoma from The Cancer Genome Atlas dataset revealed a particular signature characterized by high CD8⁺ Treg score and elevated Gal-1 expression, which delineates poor prognosis in human CRC. Our findings identify CD8⁺CD122⁺PD-1⁺ Tregs as a target of the immunoregulatory activity of Gal-1, suggesting a potential immunotherapeutic strategy for the treatment of CRC.Centro de Investigaciones Inmunológicas Básicas y Aplicada

    What Can We Learn from Multi-Objective Meta-Optimization of Evolutionary Algorithms in Continuous Domains?

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    Properly configuring Evolutionary Algorithms (EAs) is a challenging task made difficult by many different details that affect EAs&rsquo; performance, such as the properties of the fitness function, time and computational constraints, and many others. EAs&rsquo; meta-optimization methods, in which a metaheuristic is used to tune the parameters of another (lower-level) metaheuristic which optimizes a given target function, most often rely on the optimization of a single property of the lower-level method. In this paper, we show that by using a multi-objective genetic algorithm to tune an EA, it is possible not only to find good parameter sets considering more objectives at the same time but also to derive generalizable results which can provide guidelines for designing EA-based applications. In particular, we present a general framework for multi-objective meta-optimization, to show that &ldquo;going multi-objective&rdquo; allows one to generate configurations that, besides optimally fitting an EA to a given problem, also perform well on previously unseen ones
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