The Spectrum of Balanced P^(3)(1, 5)-Designs

Given a 3-uniform hypergraph H(3), an H(3)-decomposition of the complete hypergraph K(3)_v is a collection of hypergraphs, all isomorphic to H(3), whose edge sets partition the edge set of K(3)_v. An H(3)-decomposition of K(3)_v is also called an H(3)-design and the hypergraphs of the partition are said to be the blocks. An H(3)-design is said to be balanced if the number of blocks containing any given vertex of K(3)_v is a constant. In this paper, we determine completely, without exceptions, the spectrum of balanced P(3)(1 5)-designs

The laminA/NF-Y protein complex reveals an unknown transcriptional mechanism on cell proliferation

Lamin A is a component of the nuclear matrix that also controls proliferation by largely unknown mechanisms. NF-Y is a ubiquitous protein involved in cell proliferation composed of three subunits (-YA -YB -YC) all required for the DNA binding and transactivation activity. To get clues on new NF-Y partner(s) we performed a mass spectrometry screening of proteins that co-precipitate with the regulatory subunit of the complex, NF-YA. By this screening we identified lamin A as a novel putative NF-Y interactor. Co-immunoprecipitation experiments and confocal analysis confirmed the interaction between the two endogenous proteins. Interestingly, this association occurs on euchromatin regions, too. ChIP experiments demonstrate lamin A enrichment in several promoter regions of cell cycle related genes in a NF-Y dependent manner. Gain and loss of function experiments reveal that lamin A counteracts NF-Y transcriptional activity. Taking advantage of a recently generated transgenic reporter mouse, called MITO-Luc, in which an NF-Y–dependent promoter controls luciferase expression, we demonstrate that lamin A counteracts NF-Y transcriptional activity not only in culture cells but also in living animals. Altogether, our data demonstrate the occurrence of lamin A/NF-Y interaction and suggest a possible role of this protein complex in regulation of NF-Y function in cell proliferatio

HDAC1 inhibition by MS-275 in mesothelial cells limits cellular invasion and promotes MMT reversal

Peritoneal fibrosis is a pathological alteration of the peritoneal membrane occurring in a variety of conditions including peritoneal dialysis (PD), post-surgery adhesions and peritoneal metastases. The acquisition of invasive and pro-fibrotic abilities by mesothelial cells (MCs) through induction of MMT, a cell-specific form of EMT, plays a main role in this process. Aim of this study was to evaluate possible effects of histone deacetylase (HDAC) inhibitors, key components of the epigenetic machinery, in counteracting MMT observed in MCs isolated from effluent of PD patients. HDAC inhibitors with different class/isoform selectivity have been used for pharmacological inhibition. While the effect of other inhibitors was limited to a partial E-cadherin re-expression, MS-275, a HDAC1-3 inhibitor, promoted: (i) downregulation of mesenchymal markers (MMP2, Col1A1, PAI-1, TGFβ1, TGFβRI) (ii) upregulation of epithelial markers (E-cadherin, Occludin), (iii) reacquisition of an epithelial-like morphology and (iv) marked reduction of cellular invasiveness. Results were confirmed by HDAC1 genetic silencing. Mechanistically, MS-275 causes: (i) increase of nuclear histone H3 acetylation (ii) rescue of the acetylation profile on E-cadherin promoter, (iii) Snail functional impairment. Overall, our study, pinpointing a role for HDAC1, revealed a new player in the regulation of peritoneal fibrosis, providing the rationale for future therapeutic opportunities

Modelo experimental de enfermedad de Alzheimer esporádica en ratas inducido por la inyección intracerebroventricular de estreptozotocina

La enfermedad de Alzheimer esporádica (EAE) es la patología neurodegenerativa más frecuente, se acompaña de un progresivo déficit de memoria, deterioro cognitivo y cambios de personalidad. Asimismo, se caracteriza por la formación de placas neuríticas y ovillos neurofibrilares intraneuronales, degeneración neuronal y alteración del metabolismo energético cerebral, La combinación de un diagnóstico temprano y una terapia efectiva resulta imprescindible para frenar el progresivo aumento de casos dado por la mayor expectativa de vida. Para contribuir a superar esta problemática numerosos modelos animales in vitro e in vivo están siendo estudiados. Un modelo animal propuesto para el estudio de la EAE consiste en la administración intracerebroventricular (icv) de una droga diabetogénica, la estreptozotocina (STZ). En este contexto, nuestro objetivo general es el desarrollo de estrategias terapéuticas de avanzada que nos permitan prevenir y/o subsanar los cambios degenerativos que ocurren en el cerebro con Alzheimer experimental.Facultad de Ciencias Médica

Modelo experimental de enfermedad de Alzheimer esporádica en ratas inducido por la inyección intracerebroventricular de estreptozotocina

La enfermedad de Alzheimer esporádica (EAE) es la patología neurodegenerativa más frecuente, se acompaña de un progresivo déficit de memoria, deterioro cognitivo y cambios de personalidad. Asimismo, se caracteriza por la formación de placas neuríticas y ovillos neurofibrilares intraneuronales, degeneración neuronal y alteración del metabolismo energético cerebral, La combinación de un diagnóstico temprano y una terapia efectiva resulta imprescindible para frenar el progresivo aumento de casos dado por la mayor expectativa de vida. Para contribuir a superar esta problemática numerosos modelos animales in vitro e in vivo están siendo estudiados. Un modelo animal propuesto para el estudio de la EAE consiste en la administración intracerebroventricular (icv) de una droga diabetogénica, la estreptozotocina (STZ). En este contexto, nuestro objetivo general es el desarrollo de estrategias terapéuticas de avanzada que nos permitan prevenir y/o subsanar los cambios degenerativos que ocurren en el cerebro con Alzheimer experimental.Facultad de Ciencias Médica

SMO Inhibition Modulates Cellular Plasticity and Invasiveness in Colorectal Cancer

Colon Cancer (CC) is the fourth most frequently diagnosed tumor and the second leading cause of death in the USA. Abnormalities of Hedgehog pathway have been demonstrated in several types of human cancers, however the role of Hedgehog (Hh) in CC remain controversial. In this study, we analyzed the association between increased mRNA expression of GLI1 and GLI2, two Hh target genes, and CC survival and recurrence by gene expression microarray from a cohort of 382 CC patients. We found that patients with increased expression of GLI1 showed a statistically significant reduction in survival. In order to demonstrate a causal role of Hh pathway activation in the pathogenesis of CC, we treated HCT 116, SW480 and SW620 CC cells lines with GDC-0449, a pharmacological inhibitor of Smoothened (SMO). Treatment with GDC-0449 markedly reduced expression of Hh target genes GLI1, PTCH1, HIP1, MUC5AC, thus indicating that this pathway is constitutively active in CC cell lines. Moreover, GDC-0449 partially reduced cell proliferation, which was associated with upregulation of p21 and downregulation of CycD1. Finally, treatment with the same drug reduced migration and three-dimensional invasion, which were associated with downregulation of Snail1, the EMT master gene, and with induction of the epithelial markers Cytokeratin-18 and E-cadherin. These results were confirmed by SMO genetic silencing. Notably, treatment with 5E1, a Sonic Hedgehog-specific mAb, markedly reduced the expression of Hedgehog target genes, as well as inhibited cell proliferation and mediated reversion toward an epithelial phenotype. This suggests the existence of a Hedgehog autocrine signaling loop affecting cell plasticity and fostering cell proliferation andmigration/invasion in CC cell lines. These discoveries encourage future investigations to better characterize the role of Hedgehog in cellular plasticity and invasion during the different steps of CC pathogenesis.Peer reviewe

Inhaled tobramycin in children with acute bacterial rhinopharyngitis.

Antibiotic abuse for treating rhinopharyngitis induces the occurrence of resistant bacteria. As topical drugs might reduce this phenomenon, the aims of our study were to evaluate inhaled tobramycin in children with acute bacterial rhinopharyngitis and to compare it with oral amoxicillin/clavulanate. The trial was conducted as randomized, parallel group and double blind. Children, aged 3–6 years, with acute bacterial rhinopharyngitis were treated with 15 mg of aerosolized tobramycin (Group A) or 50 mg/Kg of amoxicillin/clavulanate (Group B) twice daily for 10 days. The following parameters were assessed: nasal obstruction, mucopurulent rhinorrhea, post-nasal drip, adenoidal hypertrophy, tympanic inflammation, tympanogramm, rhinomanometry and cultures. Of 416 patients screened, 311 children (178 females and 133 males), median age 4.5 years, completed the study: 156 in Group A and 155 in Group B. Both treatments improved all parameters (p<0.01 for all). Intergroup analysis showed that inhaled tobramycin indu..

Estudio morfométrico del hipocampo cerebral de animales con enfermedad de Alzheimer experimental

La enfermedad de Alzheimer esporádico (EAe) es la patología neurodegenerativa más común y se caracteriza clínicamente por una progresiva pérdida de memoria y deterioro cognitivo siendo el hipocampo (Hc) una de las regiones cerebrales más afectada. Recientemente, se ha sugerido que la EAe es una enfermedad metabólica en la cual la utilización de la glucosa y la producción de energía en el cerebro se encuentran disminuidas. Evidencia consistente que apoya este concepto proviene de estudios experimentales en animales inyectados por vía intracerebroventricular (icv) con dosis bajas la droga diabetogénica estreptozotocina (STZ), el modelo animal STZ-icv. Este modelo de EAe es ampliamente utilizado debido a que se observan anomalías estructurales, neuroquímicas, y comportamentales que coinciden con las descriptas en tal neuropatología. Recientemente pusimos a punto este modelo animal en nuestro laboratorio y demostramos que, 25 y 100 días post inyección de STZ, los animales presentan déficit en la memoria de reconocimiento de objeto nuevo y en la memoria espacial, un aumento del comportamiento símil depresión y ansiedad. Objetivos: 1) Analizar los cambios en la neurogénesis, la neurodegeneración, la gliosis y la morfología del Hc de ratas con dos dosis de STZ-icv. 2) Evaluar el estrés oxidativo en la corteza de animales con dos dosis de STZ-icv.Facultad de Ciencias Médica

Identification of a novel quinoline-based DNA demethylating compound highly potent in cancer cells

Background DNA methyltransferases (DNMTs) are epigenetic enzymes involved in embryonic development, cell differentiation, epithelial to mesenchymal transition, and control of gene expression, whose overexpression or enhanced catalytic activity has been widely reported in cancer initiation and progression. To date, two DNMT inhibitors (DNMTi), 5-azacytidine (5-AZA) and 5-aza-2′-deoxycytidine (DAC), are approved for the treatment of myelodysplastic syndromes and acute myeloid leukemia. Nevertheless, they are chemically instable and quite toxic for healthy cells; thus, the discovery of novel DNMTi is urgent. Results Here, we report the identification of a new quinoline-based molecule, MC3353, as a non-nucleoside inhibitor and downregulator of DNMT. This compound was able, in promoter demethylating assays, to induce enhanced green fluorescence protein (EGFP) gene expression in HCT116 cells and transcription in a cytomegalovirus (CMV) promoter-driven luciferase reporter system in KG-1 cells. Moreover, MC3353 displayed a strong antiproliferative activity when tested on HCT116 colon cancer cells after 48 h of treatment at 0.5 μM. At higher doses, this compound provided a cytotoxic effect in double DNMT knockout HCT116 cells. MC3353 was also screened on a different panel of cancer cells (KG-1 and U-937 acute myeloid leukemia, RAJI Burkitts lymphoma, PC-3 prostate cancer, and MDA-MB-231 breast cancer), where it arrested cell proliferation and reduced viability after 48 h of treatment with IC50 values ranging from 0.3 to 0.9 μM. Compared to healthy cell models, MC3353 induced apoptosis (e.g., U-937 and KG-1 cells) or necrosis (e.g., RAJI cells) at lower concentrations. Importantly, together with the main DNMT3A enzyme inhibition, MC3353 was also able to downregulate the DNMT3A protein level in selected HCT116 and PC-3 cell lines. Additionally, this compound provided impairment of the epithelial-to-mesenchymal transition (EMT) by inducing E-cadherin while reducing matrix metalloproteinase (MMP2) mRNA and protein levels in PC-3 and HCT116 cells. Last, tested on a panel of primary osteosarcoma cell lines, MC3353 markedly inhibited cell growth with low single-digit micromolar IC50 ranging from 1.1 to 2.4 μM. Interestingly, in Saos-2 osteosarcoma cells, MC3353 induced both expression of genes and mineralized the matrix as evidence of osteosarcoma to osteoblast differentiation. Conclusions The present work describes MC3353 as a novel DNMTi displaying a stronger in cell demethylating ability than both 5-AZA and DAC, providing re-activation of the silenced ubiquitin C-terminal hydrolase L1 (UCHL1) gene. MC3353 displayed dose- and time-dependent antiproliferative activity in several cancer cell types, inducing cell death and affecting EMT through E-cadherin and MMP2 modulation. In addition, this compound proved efficacy even in primary osteosarcoma cell models, through the modulation of genes involved in osteoblast differentiation.This work was supported by COST Action CM1406 (PBA, LA, AM, SV); by Ricerca Finalizzata 2013 PE-2013-02355271 (AM); by PRIN 2016 (prot. 20152TE5PK) (AM, LA); by AIRC grants n. 19162 (AM), 17217 (LA), and 18843 (MT); by NIH funds n. R01GM114306 (AM) and BLUEPRINT n. 282510 (AM, LA); by Programma VALERE: Vanvitelli per la Ricerca (LA) and the Italian-Flag Project-EPIGEN (LA); and by Pasteur Institute-Cenci Bolognetti Foundation (MT). MS was supported by a Waxweiler grant for cancer prevention research from the Action Lions Vaincre le Cancer. CF is a recipient of a Télévie Luxembourg fellowship. The work at LBMCC was supported by the Recherche Cancer et Sang foundation, by the Recherches Scientifiques Luxembourg association, by the Een Häerz fir kriibskrank Kanner association, by the Action LIONS Vaincre le Cancer association, and by Télévie Luxembourg. MD was supported by the Research Institute of Pharmaceutical Sciences, College of Pharmacy, Seoul National University, Korea; the Tumor Microenvironment GCRC (2011-0030001) from the National Research Foundation funded by the Ministry of Science and ICT of Korea; the Creative-Pioneering Researchers Program through Seoul National University (SNU) [Funding number: 370C-20160062]; and Brain Korea (BK) 21 Plus program, Korea