Federal University of Piau

Teresina, Brazil

Federal University of Piau

Teresina, Brazil
SEARCH FILTERS
Time filter
Source Type

Torres-Martin M.,Hospital Universitario La Paz | Lassaletta L.,Hospital Universitario La Paz | Isla A.,Hospital Universitario La Paz | Pinto G.R.,Federal University of Piau | And 4 more authors.
Genes Chromosomes and Cancer | Year: 2015

Schwannomas are tumors that develop from Schwann cells in the peripheral nerves and commonly arise from the vestibular nerve. Vestibular schwannomas can present unilaterally and sporadically or bilaterally when the tumor is associated with neurofibromatosis Type 2 (NF2) syndrome. The molecular hallmark of the disease is biallelic inactivation of the NF2 gene. The epigenetic signature of schwannomas remains poorly understood and is mostly limited to DNA methylation of the NF2 gene, whose altered expression due to epigenetic factors in this tumor is controversial. In this study, we tested the genomewide DNA methylation pattern of schwannomas to shed light on this epigenetic alteration in these particular tumors. The methodology used includes Infinium Human Methylation 450K BeadChip microarrays in a series of 36 vestibular schwannomas, 4 nonvestibular schwannomas, and 5 healthy nerves. Our results show a trend toward hypomethylation in schwannomas. Furthermore, homeobox (HOX) genes, located at four clusters in the genome, displayed hypomethylation in several CpG sites in the vestibular schwannomas but not in the nonvestibular schwannomas. Several microRNA (miRNA) and protein-coding genes were also found to be hypomethylated at promoter regions and were confirmed as upregulated by expression analysis; including miRNA-21, Met Proto-Oncogene (MET), and PMEPA1. We also detected methylation patterns that might be involved in alternative transcripts of several genes such as NRXN1 or MBP, which would increase the complexity of the methylation and expression patterns. Overall, our results show specific epigenetic signatures in several coding genes and miRNAs that could potentially be used as therapeutic targets. © 2014 Wiley Periodicals, Inc.


Bezerra M.C.,Federal University of Pernambuco | Melo R.,Federal University of Pernambuco | Melo R.,Federal Institute of Education | Dantas J.,Federal University of Pernambuco | And 3 more authors.
Conference Proceedings - IEEE International Conference on Systems, Man and Cybernetics | Year: 2014

Cloud computing environments are an emerging technology that aims at proving several cloud services over the Internet, making it possible to provide a huge variety of applications with different purposes to users. Multimedia services are examples of these new services that use cloud computing, like video streaming, where the user can access their videos from cloud environments. For cloud service systems, assurance of high-availability of cloud services is a challenging and critical issue. In this paper, we evaluated the video streaming service's availability for video on demand cloud system. Hierarchical modeling strategy, availability models combining reliability blocks diagrams (RBD) and continuous time Markov chain (CTMC) were used, indicating a system availability of 1.92 nines. The critical component of the system was indicated through sensibility analysis. We realized a model validation technique to demonstrate that the models represent the behavior of the real system. © 2014 IEEE.


Torres-Martin M.,Hospital Universitario La Paz | Pena-Granero C.,Hospital Universitario La Paz | Carceller F.,Hospital Universitario La Paz | Gutierrez M.,Hospital Universitario La Paz | And 5 more authors.
Molecular Cytogenetics | Year: 2014

Background: Pediatric oligodendrogliomas are rare and appear to show a different molecular profile from adult tumors. Some gliomas display allelic losses at 1p/19q in pediatric patients, although less frequently than in adult patients, but this is rare in tumors with an oligodendroglial component. The molecular basis of this genomic abnormality is unknown in pediatric gliomas, but it represents a relatively common finding in pediatric oligodendroglioma-like neoplasms with leptomeningeal dissemination. Results: Multiplex ligation-dependent probe amplification (MLPA) analysis using SALSA P088-B1 for the analysis of the 1p/19q allelic constitution in a pediatric anaplastic (oligodendro)-glioma showed homozygous co-deletion for markers: TNFRSF4 (located at 1p36.33), TP73 (1p36.32), PPAP2B (1pter-p22.1), DPYD (1p21.3), and PDCD5 (19q13.12), and hemizygous deletion of BAX (19q13.3-q13.4). No sequence changes for R132 and R172 of the IDH1/2 genes were identified. Conclusions: The molecular findings in this pediatric anaplastic glioma do not allow for a clearly definitive pathological diagnosis. However, the findings provide data on a number of 1p/19q genomic regions that, because of homozygotic deletion, might be the location of genes that are important for the development and clinical evolution of some malignant gliomas in children. © 2014 Torres-Martín et al.; licensee BioMed Central Ltd.


Torres-Martin M.,Hospital Universitario La Paz | Lassaletta L.,Hospital Universitario La Paz | Isla A.,Hospital Universitario La Paz | De Campos J.M.,Fundacion Jimenez Diaz | And 5 more authors.
Oncology Reports | Year: 2014

Schwannomas and grade I meningiomas are non-metastatic neoplasms that share the common mutation of gene NF2. They usually appear in neurofibromatosis type 2 patients. Currently, there is no drug treatment available for both tumors, thus the use of wide expression technologies is crucial to identify therapeutic targets. Affymetrix Human Gene 1.0 ST was used to test global gene expression in 22 meningiomas, 31 schwannomas and, as non-tumoral controls, 3 healthy meningeal tissues, 8 non-tumoral nerves and 1 primary Schwann cell culture. A non-stringent P-value cut-off and fold change were used to establish deregulated genes. We identified a subset of genes that were upregulated in meningiomas and schwannomas when compared to their respectively healthy tissues, including PDGFD, CDH1 and SLIT2. Thus, these genes should be thoroughly studied as targets in a possible combined treatment.


PubMed | Hospital Universitario La Paz, Federal University of Piau, Fundacion Jimenez Diaz, University of Navarra and 2 more.
Type: Comparative Study | Journal: Oncology reports | Year: 2014

Schwannomas and grade I meningiomas are nonmetastatic neoplasms that share the common mutation of gene NF2. They usually appear in neurofibromatosis type 2 patients. Currently, there is no drug treatment available for both tumors, thus the use of wide expression technologies is crucial to identify therapeutic targets. Affymetrix Human Gene 1.0 ST was used to test global gene expression in 22 meningiomas, 31 schwannomas and, as non-tumoral controls, 3 healthy meningeal tissues, 8 non-tumoral nerves and 1 primary Schwann cell culture. A non-stringent P-value cut-off and fold change were used to establish deregulated genes. We identified a subset of genes that were upregulated in meningiomas and schwannomas when compared to their respectively healthy tissues, including PDGFD, CDH1 and SLIT2. Thus, these genes should be thoroughly studied as targets in a possible combined treatment.


Rocha Gontijo J.A.,University of Campinas | Gui D.C.,University of Campinas | Boer P.A.,University of Campinas | Dos Santos A.R.,Federal University of Piau | And 3 more authors.
Clinical and Experimental Hypertension | Year: 2010

The aim of this study was to evaluate the arterial blood pressure and renal function of female rats in persistent estrus. Twenty-five female Wistar-Hannover rats were randomly divided into two groups: Group I (control, n 15) and experimental (persistent estrus, n 10). A tail-cuff system was used to measure blood pressure at 12 weeks of life. Parameters to evaluate renal function were taken into consideration. A significant increase in arterial pressure and a significant decrease in fractional sodium excretion were found in the androgenized animals compared to controls. There was no difference between the two groups with respect to glomerular filtration rate or in fractional potassium excretion. An increase in blood pressure and a reduction in fractional sodium excretion occur in female rats in persistent estrus. © 2010 Informa UK Ltd.


Lopes-Costa P.V.,Federal University of Piau | Dos Santos A.R.,Federal University of Piau | Dos Santos L.G.,Federal University of Piau | Da Silva B.B.,Federal University of Piau
Cell Proliferation | Year: 2010

Objectives: To evaluate the effect of raloxifene on Ki-67 and Bcl-2 antigen expression in operable, stage II, oestrogen-receptor-positive invasive ductal breast carcinomas. Materials and methods: Twenty post-menopausal women who had taken 60 mg of raloxifene daily for 28 days prior to definitive surgery were enrolled in the investigation. Two tumour samples were obtained by incisional biopsy during the study, one at the time of confirmation of diagnosis of invasive ductal carcinoma and evaluation of oestrogen receptor status, and the other 29 days later, at the time of definitive surgery. Immunohistochemistry was performed on tumour samples, prior to and after raloxifene treatment, to evaluate Ki-67 and Bcl-2 expression. Friedman and McNemar tests were used for statistical analysis of the data, significance being established at 5%. Results: Mean percentage of Ki-67-stained nuclei was 24.86 ± 2.95 prior to raloxifene treatment and 13.33 ± 1.52 after treatment (P < 0.001). Prior to raloxifene treatment, only 9/20 cases (45%) were classified as Bcl-2-positive, whereas after treatment, 17/20 (85%) were classified as Bcl-2-positive (P < 0.013). Conclusions: Raloxifene treatment significantly reduced Ki-67 antigen expression and increased Bcl-2 expression in breast carcinomas of post-menopausal women. © 2010 Blackwell Publishing Ltd.


Da Silva Filho E.C.,Federal University of Piau | Monteiro P.D.R.,Federal University of Piau | Sousa K.S.,University of Campinas | Airoldi C.,University of Campinas
Journal of Thermal Analysis and Calorimetry | Year: 2011

In this work Chitosan (Ch) was chemically modified with ethylenesulfide (Es) under solvent-free conditions to give (ChEs), displaying a high content of thiol groups due to opening of the three member cyclic reagent. ChEs was used in studies of lead and cadmium adsorption from aqueous solution, using the batchwise method and calorimetric studies were accomplished to those interactions, through the calorimetric titration technique. The obtained results show that the modified Ch, ChEs is a material, that besides presenting the advantages of being a biopolymer, it showed a good adsorption capacity of the lead and cadmium cation metallic, that are extremely poisonous and harmful to the environment. The results of the calorimetric titration showed that the related thermodynamic parameters to those adsorptions shown favorable thermodynamic data. © 2011 Akadémiai Kiadó, Budapest, Hungary.

Loading Federal University of Piau collaborators
Loading Federal University of Piau collaborators