Navegando por Orientadores "OLIVEIRA, Edivaldo Herculano Correa de"

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Análise de alterações no número de cópias envolvendo os cromossomos 1p e 22 em meningiomas de baixo grau
(Universidade Federal do Pará, 2013-12-13) SILVA, Geanny Pereira da; OLIVEIRA, Edivaldo Herculano Correa de; http://lattes.cnpq.br/0094007714707651
Meningiomas are the second most common type of primary brain tumor, originating in the meninges covering the brain and spinal cord. They show slow growth, and are found more often in the CNS, being benign in most case, although there are also cases of meningiomas classified as malignant. At the cytogenetic level, meningiomas are the most well studied tumors in humans: studies in CNS tumors have shown that most cases had chromosomal abnormalities, and the most common alterations in theis type of tumor are the loss of one copy of chromosome 22 and deletion of the short arm of chromosome 1. These alterations have been associated with the tumorigenesis process, because they are found mostly in low-grade tumors, particularly deletions involving chromosome 22. Thus, the aim of this study was to analyze the occurrence of copy number alterations (CNAs) involving chromosomes 1p and 22 meningiomas grade I and II, and in addition to verifying the existence of other recurrent rearrangements through the application of high resolution comparative genomic hybridization (array - CGH ). Tumor samples were collected from eight patients. All samples showed gains and losses of various chromosomal segments. Except for one case, all others showed, in different degrees though, more deletions than amplifications. Loss of 1p segments was observed in all samples. Some CNAs were recurrent, being found up to six out of the eight cases. Pair 22 showed CNV in all samples, but the total monosomy was observed in only two of the eight samples. The global analysis of CNAs in all samples showed that, although changes 1p and 22 were the most frequent observed alterations, as expected, other genomic regions had also alterations in various samples, indicating a possible involvement of these modifications in the process of tumorigenesis and tumor progression. For instance, alterations in pairs 9, 12 and 17, have been observed in other studies and were correlated with atypical and anaplastic meningiomas. Our data indicate the existence of a larger number of genomic alterations in low-grade meningiomas, disagreeing partly with the assumption that these tumors are characterized by a small number of changes, usually involving pair 22 and, less frquently, loss of 1p. However, the fact that these tumors present alterations that are classically found in meningiomas, even benign, such as deletions in 1p and 22q, may be an indication that these changes must be linked with the early events of origin in meningiomas, as already suggested several times by other authors . In conclusion, these alterations remain important markers in meningiomas, and the relationships of these and other CNAs with the response to different treatments and recurrences should be the next step after cytogenomic characterization based on array-CGH has been completed.
Acesso aberto (Open Access)
Análise genômica comparativa e os polimorfismos nos genes TNFA, IFNG IL6 e IL10 associados à expressão de citocinas na infecção por Plasmodium vivax no município do Itaituba, Estado do Pará
(Universidade Federal do Pará, 2018-07-19) PIMENTA, Tamirys Simão; MACHADO, Ricardo Luiz Dantas; http://lattes.cnpq.br/0307356330748427; OLIVEIRA, Edivaldo Herculano Correa de; http://lattes.cnpq.br/0094007714707651
In endemic areas of Asia, Oceania, Central and South America and in the horn of Africa P. vivax malaria is a major cause of morbidity with 35 million cases annually. In Brazil, the Amazon region concentrates almost all cases and infections registered countrywide, with more than three hundred thousand cases per year. Several evidences suggest that an exacerbated inflammatory response associated to density parasite is likely to aggravate the malaria symptoms. We assessed the haematological and immunological aspects, genetic alterations related to CNVs that could lead to phenotypic alterations, conferring resistance or susceptibility to malaria, as well the presence of polymorphisms in cytokine genes and their association with the infection in patients living in a gold-mining area in a gold-mining in the Brazilian Amazon Region, establishing patterns of immune response characteristic of primary malaria, recurrent malaria and endemic control. Six SNPs (TNFA-308G/A, IFNG+874T/A, IL6-174G/C, IL10-1082G/A, -819C/T, -592C/A) in four genes were determined; blood cell count was conducted on automatic analyzer; plasmatic cytokines IL-6, IL-10, TNF-α and IFN-γ were quantified by flow cytometry and density parasite was estimated by thick blood films with confirmation by nested-PCR; the CNV was estimated by aCGH and association between copy number and phenotypes (parasite load, mean number of clinical infections of malaria and gender) was assessed. The statistical analyzes were performed by Graph-pad prism 6.0 and Bioestat 5.0. No significant association was found between SNPs and malaria infection; cytokine levels were higher in malaria group when compared to endemic control; production of IL-10 was higher in the presence of GCC/GCC haplotype; IFN-γ levels were correlated with previous malaria episodes; malaria patients showed lower platelet numbers, reduction on white blood cells count and an increased monocyte percentage; significant increase in the IL-6 and IL-10 plasmatic levels in both malaria groups; the primary malaria patients displayed the highest significant plasmatic IFN-γ levels; recurrent malaria patients displayed the highest significant plasmatic TNF-α; malaria infection demonstrated correlation between parasite density and TNF-α, IL-6 and IL-10 levels; a total of 112 amplified genes and 12 deleted genes were observed and the CNVs found did not include any gene related to receptors or vivax malaria resistance factors. There were no statistically significant correlations between the clinical and pathological data (parasite load, mean number of clinical infections of malaria and gender) and the presence of CNVs in the patients studied. This study provides additional data on Plasmodium-host immune response and describes the quantitative changes in the human genome in P. vivax infection in an endemic area of garimpo.
Acesso aberto (Open Access)
Análise transcriptômica das linhagens celulares B103 e C6 expostas à ação do metilmercúrio
(Universidade Federal do Pará, 2023-04) BONFIM, Laís Teixeira; FERREIRA, Wallax Augusto Silva Ferreira; OLIVEIRA, Edivaldo Herculano Correa de; http://lattes.cnpq.br/009400771470765; https://orcid.org/0000-0001-6315-3352
The intensification of anthropogenic activities produces a high rate of environmental pollution, mainly in water bodies, where the contamination by metals has become an object of great interest, due to their inability to support such load. Mercury (Hg) is a naturally occurring metal that can be used in the manufacture of home products such as fluorescent lamps, fungicides, and germicides. The entry of Hg into the food chain occurs through the methylation of Hg2+ ions into MeHg. After methylation, Hg is considered highly toxic to humans, and among the main target organs of this intoxication we can mention the brain, since MeHg easily crosses the blood-brain barrier and can accumulate in different brain areas. It is known that, once in the CNS, MeHg can cause extensive cellular damage, such as DNA damage, oxidative stress, neuroinflammation and cell death in both neurons and glial cells. Thus, the objective of this study was to analyze the transcriptomic alterations of cell lines B103 and C6, derived from neuroblastoma and glioma of Rattus norvegicus, exposed to the action of methylmercury. For this, the expression microarray technique was used to evaluate the global profile of gene expression after 24h of MeHg exposure. Our results demonstrate that MeHg induces significant alterations in gene expression of the two cell lines evaluated. The alterations were more prominent in the C6 cell line, in which a greater amount of differentially expressed genes was observed. Among the genes differentially expressed of the B103 cells we can highlight the genes Cdc42se2 (log2 FC -4.055713), Dcx (log2 FC 3.618981) and 4930449C09Rik (log2 FC 3.5129156) at a concentration of 0.1 μM. As for the exposure of 2.8 μM, the genes with the highest FC were Crem (log2 FC -4.027875), Otoa (log2 FC 3.501512) and Dcx (log2 FC 3.423433). In addition to the abovementioned genes, the genes Trim14, Gm14169, Gm30871, Otoa and Dcx were shared between the two exposed groups. As for the C6 lineage, ten transcripts with FC above 3 (Aldh1l2, Dac1, Rps4l, Zbtb46, 6430573p05Rik, Tcf12, Awat2, Muc3, Dclre1b, Slc38a6) are highlighted. In the 6.3 μM treatment, only three genes were altered more than 3 times (Rps4l, Ankdr44 and 2610318N02Rik). It is also noteworthy that three genes were shared between treatments (Rps4l, Lamb 3 and Gm 41386).
Acesso aberto (Open Access)
Aplicação de pintura cromossômica em espécies da família Accipitridae (Aves, Falconiformes): considerações filogenéticas e evolutivas
(Universidade Federal do Pará, 2013-10-18) TAGLIARINI, Marcella Mergulhão; OLIVEIRA, Edivaldo Herculano Correa de; http://lattes.cnpq.br/0094007714707651
Cytogenetic analyses of Falconiformes have showed that Accipitridae have atypical chromosomal organization among birds, with relatively low diploid numbers (mean of 2n=66) and a few pairs of microchromosomes (4 to 6 pairs). Proposals based on classical cytogenetics suggested that this fact was a result of fusions of microchromosomes found in the Avian putative ancestor karyotype. With the aim of contributing to clarify questions concerning chromosomal evolution and phylogenetics of this family, we analyzed three species of subfamily Buteoninae (Rupornis magnirostris, Buteogallus meridionales e Asturina nítida) and two of subfamily Harpiinae (Harpia harpyja e Morphnus guianensis) by means of classical and molecular cytogenetics. Buteoninae species showed karyotypes with diploid number 68 and FN varying from 100 to 102; the number of biarmed chromosomes varied between 17 and 21, Z chromosome was submetacentric and W chromosome was metacentric in R. magnirostris and submetacentric in Asturina nitida. 18/28 rDNA probes showed that nucleolar organizer regions are located in a medium-sized submetacentric pair, corresponding to the short arm of pair 7. Telomeric sequences were found not only on terminal region of the chromosomes, but also on some interstitial regions. Whole-chromosome paints derived from pairs 1 to 11 of Gallus gallus (GGA) produced the same number of signals in these species. The availability of whole-chromosome probes derived of Leucopternis albicollis confirmed the presence of a common cytogenetic signature for Buteoninae species, corresponding to the association between GGA1p and GGA6. An interstitital telomeric sequence found in this pair reinforces this fact. Concerning the species of Harpiinae, the conventional staining analyses showed that H. harpyja and M. guianensis have 2n=58 and 2n=56, respectively. Both species have 22 pairs of biarmed chromosomes, although H. harpyja has two more chromosomes than M. guianensis. 18/28S rDNA mapped on the short arm of pair 1 in M. guianensis and in two pairs in H, harpyja (6 and 25). Telomeric sequences were found on the terminal regions, but also on interstitial locations in some chromosomes. Despite the apparent karyotypic similarity, no common associations were found in these two species. The different associations observed in Morphnus and Harpia indicate that these species suffered an extensive genomic reorganization after their separation in two independent lineages. Moreover, the absence of shared associations suggests that the fissions of macrochromosomes have occurred in the common ancestor of this group, and that fusions were subsequent to their isolation as different lineages. Our results, together with previous reports in other species of Accipitridae, indicate that the processes of fissions involving the macrochromosomes of GGA and fusions between these segments and between them and microchromosomes are recurrent rearrangements in this group. Although Falconidae species also show atypical karyotypes, with low diploid numbers, global cytogenetic data of Accipitridae indicate that, similarly to the morphological traits between these two families, the rearranged karyotypes would correspond to homoplasies, from the evolutionary point of view, supporting the idea that these families do not form a monophyletic group.
Acesso aberto (Open Access)
Caracterização do genoma de tumores bem diferenciados da tireóide por hibridização genômica comparativa em matriz (aCGH)
(Universidade Federal do Pará, 2014-03-31) ALMEIDA, Deise Cibele Nunes de; OLIVEIRA, Edivaldo Herculano Correa de; http://lattes.cnpq.br/0094007714707651
More than 95% of thyroid gland malignancies are well-differentiated tumors. Preoperative diagnosis accuracy for papillary carcinomas, based on FNAC (Fine Needle Aspiration Cytology) and ultrasound screenings, has become nearly 100%. Nevertheless, when follicular neoplasm diagnosis is concerned, this reality is quite different. Using current preoperative screening tools, 60 – 80% of patients suspected to present follicular thyroid cancer, when operated turn out to suffer from benign disease. Therefore, in an effort to improve these results, genomic analysis of Copy Number Variations (CNV) that may more precisely differentiate follicular tumor from other thyroid conditions were carried out in 13 patients (3 bearing goiters, 2 hyperplasias, 4 follicular adenomas, 4 follicular carcinomas, 1 healthy individual). CNVs were tracked through aCGH method in order to detect follicular carcinoma most accurately. Results were compared with classic papillary carcinoma (4 subjects) and follicular variant (2 subjects). Samples demonstrated 725 CNVs, 703 of which belonging to patients with disease. Among these, 18 most frequent regions were selected. Patterns of amplification were more frequent in younger patients, while deletions were more frequent in the elder ones. Carcinoma patients presented very close CNV rates. Also, exclusive patterns of chromosomes 8 and 12 alterations were noticed in follicular carcinoma. Thus, it is possible to conclude that thyroid follicular carcinoma is a condition comprehending exclusive patterns of alterations, and progression of this disease is not related to follicular adenomas. Finally, regions -8p22 and 12p13.32-p12.33 were detected in 100% and 75% of samples respectively, therefore, may be deemed as possible tumoral markers.
Acesso aberto (Open Access)
Investigação de ocorrência de alterações moleculares nos genes KRAS, HRAS, NRAS e BRAF em carcinoma papilífero da tireóide
(Universidade Federal do Pará, 2018-01-25) PIMENTEL, Clebson Pantoja; OLIVEIRA, Edivaldo Herculano Correa de; http://lattes.cnpq.br/0094007714707651
The most common cancer of the thyroid is the papillary carcinoma (PTC), which represents 80% of the cases of cancer affecting this gland. PTC is a malignant tumor, with slow evolution, found in any age, but with a higher occurrence in patients between 30-40 years old. The metabolic pathway MAPK is the most associated with PTC. Among the several proteins which have a role in this pathway, we highlight the ones encoded by the genes belonging to families RAS and BRAF. Considering that there are few clinical and genetic studies focusing on thyroid cancer from Brazilian Amazonian region, the aim of this study was to investigate the occurrence of alterations in genes HRAS, NRAS, KRAS and BRAF in patients with PTC treated in a public hospitals, from Belém (PA), seeking to make an association between the mutations found and the biochemical and clinical findings. To achieve this goal, polymerase chain reaction (PCR) and direct automatic sequencing were used. Statistical analyses were performed using the software SPSS version 21.0. Continuous data were expressed as means and standard deviation and categorical data were described in terms of percentages. Student t Test was used to evaluate the continuous variables, while Fisher exact test and Chi-square were used to analyze categorical variables. We considered p<0.05 as significant value in all the analyses. Our results showed that, among the analyzed genes, only BRAF showed a mutation, BRAFV600E, in 21 out of the 53 patients (16 female and 5 males, 39.6%). Additionally, a new mutation in codon 38 of gene K-RAS was found (p.D38E). Considering clinical data, we found a significant association between the BRAFV600E mutation and hoarseness, as well as between this mutation and lymph node metastasis. In addition, the observation of a new mutation in the K-RAS gene indicates that the number of gene changes involving the MAPK pathway is still incomplete. The data obtained can be used for a better pre-surgical evaluation of thyroid tumors, in order to increase the sensitivity for the detection of cancer and avoid unnecessary surgeries of lesions erroneously identified as malignant.
Acesso aberto (Open Access)
Screening de polimorfismos e análise comparativa de alterações no número de copias do gene tp53 em gliomas
(Universidade Federal do Pará, 2012-01-24) BRITO, José Reginaldo Nascimento; OLIVEIRA, Edivaldo Herculano Correa de; http://lattes.cnpq.br/0094007714707651
Astrocytic neoplasms comprises around 60% of the Central Nervous System tumors, affecting mainly adults in a highly productive phase of life, and showing poor prognosis despite of the available treatments. A better knowledge of the molecular biology of this group of tumors is necessary to understand their evolution and to plan the treatment in a better way, as well as to develop new therapies. Hence, this study had the aim the analysis of modifications of gene TP53 related to changes in the number of copies and the presence of polimorphisms in exons 4 to 11, considered hotspots for mutations. A total of 14 samples of different malignant grades were analyzed by interphasic FISH using locus-specific probes for gene TP53 and centromeric for chromosome 17, and by SSCP for screening polymorphism in exons 4 to 11. The results were compared between tumors with grades I and II (benign) to those with grades III and IV (malign). The results concerning the locus specific probes (gene TP53 and centromere of chromosome 17) showed that the occurrence of deletions and amplifications were statistically important when compared to nuclei with normal copy number. However, these alterations were not related to the age, sex or malignancy. On the other hand, these alterations were found more frequently in patients with tumors with intermediate grades (III). SSCP experiments revealed polymorphisms in exons 5, 7 and 10, and although they were not realted to the malignancy of tumors, the samples with polymorphism corresponded to the patients with shorter survival after treatment, suggesting a relation between the mutations in these exons and higher aggressively tumors.
Acesso aberto (Open Access)
Sustentabilidade Organizacional: percepção de práticas sustentáveis nos ambientes de trabalho remoto e presencial entre os servidores Técnico-Administrativos em Educação do Instituto de Ciências Exatas e Naturais da UFPA
(Universidade Federal do Pará, 2023-02-10) BEZERRA, Thiago de Matos; OLIVEIRA, Edivaldo Herculano Correa de; http://lattes.cnpq.br/0094007714707651; https://orcid.org/0000-0001-6315-3352
Discussions on better use of natural resources and the global event of the COVID-19 pandemic have contributed to the expansion of changes in ways of working, so that organizations have had to adapt. In this context, there has been an expansion of remote work. In this way, a case study was carried out, with the aim of understanding how we arrived at sustainability practices in the work environment, in remote and face-to-face modalities. This is a cross-sectional study, of a descriptive nature, with pending information from a questionnaire with questions with open and closed answers, which was carried out among the load servers belonging to the career of the TechnicianAdministrative in Education, who work at the Instituto of Exact and Natural Sciences at the Federal University of Pará. The results indicated some awareness on the part of the public servants regarding this topic, regarding the similarity between the responses received in each modality, and indicated the need for the institution to continue to invest in the implementation of sustainability practices.