Dissertações em Neurociências e Biologia Celular (Mestrado) - PPGNBC/ICB

URI Permanente para esta coleçãohttps://repositorio.ufpa.br/handle/2011/2375

O Mestrado Acadêmico pertence ao Programa de Pós-Graduação em Neurociências e Biologia Celular (PPGNBC) do Instituto de Ciências Biológicas (ICB) da Universidade Federal do Pará (UFPA).

Navegar

Agora exibindo 1 - 9 de 9

Acesso aberto (Open Access)
Ação da ciclosporina A na via de ativação do fator de crescimento de nervo (NGF) em células neurais do SNP
(Universidade Federal do Pará, 2016-08-26) JESUS, Jessica Batista de; SENA, Chubert Bernardo Castro de; http://lattes.cnpq.br/8620752020290438; NASCIMENTO, José Luiz Martins do; http://lattes.cnpq.br/7216249286784978
A is an immunosuppressive drug with known action on T cells of the immune system used in organ transplantation and autoimmune diseases. In the nervous system, cyclosporin A acts by inhibiting the action of Calcineurin, an important second messenger from pathway of signal transduction Nerve Growth Factor (NGF), resulting in hyperphosphorylation of the nuclear factor of activated T cells (NFAT), and downregulation of NGF, TrkA and other factors that participating in this pathway. The NFAT1-4 family are dependent isoforms of calcineurin, while NFAT5 isoform is independent. It has been demonstrated the neuroprotective role of Cyclosporin A via calcineurin dependent or independent. In this study, we evaluate the action of Cyclosporine A in the PNS system, that could be associated with levels of NGF, TrkA and an independent of calcineurin transcription factor (NFAT5) that interplay the plasticity of neuronal cells derived from Dorsal root ganglia (DRG) maintained in cultures. We use E10 DRG cultures supplemented with medium conditioned E9 Retinal treated with Cyclosporin A for 48 and 72 hours. Cultures enriched neurons were confirmed by calcium imaging method. The action of Cyclosporine A in the neuritogenesis was assessed by bright field microscopy, expression of NGF, TrkA and NFAT5 was performed by RT-PCR, intracellular accumulation of NGF was evaluated by immunofluorescence and the presence of TrkA in neurons. The viability test of the cultures treated or not with the concentrations of 1-40μM Cyclosporine A was performed by MTT method. The results show an increase of NGF levels in mixed cultures, and TrkA receptor and NFAT5 in cultures enriched in neurons following treatment with cyclosporine A. Given the importance of NGF pathway in the development and maintenance of the SNP, the use of Cyclosporin A have activity in the peripheral nervous system cells, which might be used in the clinic with new target for new therapies.
Acesso aberto (Open Access)
Análise citogenética de duas espécies do gênero Hylaeamys (Rodentia: Cricetidae) por citogenética clássica e molecular
(Universidade Federal do Pará, 2013-04-05) PINTO, Jamilly Amaral; NAGAMACHI, Cleusa Yoshiko; http://lattes.cnpq.br/8887641213110093
Rodents are one of the largest and oldest orders of the class Mammalia. In South America, the order Rodentia compromises about 42% of mammal species, and from this more than 50% belong to the family Cricetidae, which includes the subfamily Sigmodontinae. The genus Hylaeamys is inserted in the tribe Oryzomyini and corresponds to one of 10 new genera proposed for species and species groups within Oryzomys. Hylaeamys is the equivalent of "megacephalus group", and consists of the species H. acritus, H. laticeps, H. megacephalus, H. perenensis, H. oniscus, H. tatei and H. yunganus, distributed in Venezuela, Trinidad, Guyana, Paraguay and Brazil, in areas of the Amazon rain forest, Atlantic rainforest and savannah. This study aims to analyze chromosomal markers in two species of the genus Hylaeamys, providing data to assist in its taxonomic and cytogenetic characterization. Nineteen samples of Hylaeamys megacephalus (HME) and four samples of Hylaeamys oniscus (HON) were analyzed. HME has 2n = 54 and HON, 2n = 52. The results obtained by G- and C-banding and Fluorescent In Situ Hybridization with whole chromosome probes from Hylaeamys megacephalus made it possible to determine the chromosomal characteristics of the species studied, as well as allowing a comparative analysis between them, and in comparison with Cerradomys langguthi, observing homeologies and karyotypic differences. The two species of Hylaeamys differ by a centric fission/fusion rearrangement in which HON shows the association of the pairs 14/19 of HME. This association is shared with CLA with an inversion (19/14/19). This work is an achievement for phylogeny and chromosomal studies on the genus Hylaeamys.
Acesso aberto (Open Access)
Análise da atividade enzimática de quitotriosidase como um marcador para a malária vivax: abordagens bioquímicas e moleculares
(Universidade Federal do Pará, 2010) CRUZ, Cleber Monteiro; SILVA, Luiz Carlos Santana da; http://lattes.cnpq.br/6161491684526382
Chitotriosidase was the first described chitinase and its physiologic role is not entirely clear, although many studies have been showed its participation as a component of human immune response. A 24pb duplication on exon 10 of chit1 gene results on RNAm frameshift, leading to a 87 nucleotides deletion. This alteration generates a protein with no catalytic activity at all. This condition is called chitotriosidase deficiency and presents a frequency close to 6% of homozygosis duplication in different ethnical groups. Malaria is an amazon endemic parasitosis caused by protozoaries of genus Plasmodium and causes symptoms as fever, headache and vomit, which leads to a characteristic immune response. The objective of this study was to evaluate the chitotriosidase enzyme behavior in patients suffering of malaria in Pará state and to determine the frequency of 24pb duplication on chitotriosidase gene in a representative sample. Chitotriosidase measurement was made in 100 healthy individual and in 47 malarial patients. The molecular analysis of the 24pb duplication was realized in 100 volunteers trough a protocol which included DNA extraction techniques, PCR and 2,5% agarose gel visualization to verify normal fragments (normal homozygote: 195pb) and the 24pb duplication (mutant homozygote: 219pb; heterozygote: 219pb e 195pb). This study described at first time on scientific literature the chitotriosidase plasmatic levels increasing in patients suffering of malaria vivax compared to healthy individual. No association was observed between parasitemia and plasmatic chitotriosidase levels in malarial patients. Molecular analysis showed a frequency of 72% normal homozygotes, 24% heterozygotes and 4% mutant homozygotes to 24pb duplication. Allelic frequencies were around 84% to wild allele and 16% to mutant allele. No correlation was found between genotype and biochemical phenotype (represented by chitotriosidase levels) on control group.
Acesso aberto (Open Access)
Análises moleculares da região controle do DNA mitocondrial de astrocitomas na população paraense
(Universidade Federal do Pará, 2012-06-06) COSTA JÚNIOR, Carlos Antonio da; ANSELMO, Nilson Praia; http://lattes.cnpq.br/6518287721873199
The central nervous system cancer represents 2% of all malignancies in the world population and 23% of cases of childhood cancer. In Brazil, an estimated 4,820 cases of cancer in men and women in 4450 to the year 2012. Gliomas are tumors of the central nervous system formed from glial cells, making up over 70% of brain tumors. The most important property of gliomas is the ability of immune evasion. Age, ethnicity, gender and occupation may be considered risk factors for the development of gliomas, and are twice as common in African-Americans. The astrocytoma is the most common glial tumor, constituting about 75% of cases of gliomas. These tumors are classified into four levels according to the World Health Organization. Mitochondrial DNA is related to the development and progression of various types of tumors. Mitochondrion is responsible for cellular energy balance and is involved in triggering apoptosis responding to oxidative stress. Mutations in DLOOP can change DNA replication rates and increase the developing cancer risk. We analyzed 29 samples astrocytoma classified according to the WHO. Our data suggest that low-grade astrocytomas may be related to genetic inheritance, making some patients with specific mutations or polymorphisms more susceptible to the risk of developing the disease, and high grade may be related to prolonged exposure to carcinogenics. Polymorphisms and mutations have been identified which correlate with some risk of developing astrocytomas and disease progression. The insertion of two or more nucleotides at microsatellite regions may cause instability and contribute to the cancer onset. Deletion at the site 16132 may be a high-grade astrocytoma marker, as well as insertion of two or more cytosines to the site 16190 can be an astrocytoma specific marker. Heteroplasmy may be decisive for the emergence and / or progression of high-grade astrocytomas.
Acesso aberto (Open Access)
Avaliação de biomarcadores sorológicos em um estudo de busca ativa de casos novos de hanseníase em área hiperendêmica
(Universidade Federal do Pará, 2016-10-07) GOBBO, Angélica Rita; SALGADO, Claudio Guedes; http://lattes.cnpq.br/2310734509396125
Leprosy is a cronic infection diasease clinically characterized by changes in tactile, thermal and painful sensitivity in skin and peripheral nerves. Due to the absence of laboratory diagnosis of leprosy, new tools that contribute for identification of cases are necessary for enable patient treatment before progression to physical disabilities. In this sense, the present study aimed evaluate serological biomarkers contribution for early diagnosis of leprosy. Was perfomed an active case finding study in Mosqueiro district, Belém – Pará. All individuals were clinically examined by experient leprologists doctors and than 5mL of peripheral blood were colleted for future titration of anti-ND-O-BSA, anti-LID-1 e anti-NDO-LID by ELISA. The action of active finding in Mosqueiro district diagnosed 104 new cases of leprosy between 895 subjects examined (11.6%), indicating a high hidden endemy that agree with the high seroprevalence between schoolchildren. Were observed a significant difference among patients with late or early diagnoses, mainly in multibacillary forms. All biomarkers tested showed promising results in detection of late cases, such as related in literature, however, for early cases those molecules identified correctly only 50% of patients. None of biomarker tested presented sufficient sensitivity to detect all leprosy patients, early or lately diagnosed. Besides, LID-1 molecule had evidenced a lower sensitivity for early cases, their high especificity and accuracy suggest their use as a potential tool for serological screening to identify assintomatic subjects with high risk of illness. Thus, we concludes that besides no biomarker had reveled utility as a serological diagnostic tool, the detection of anti-LID-1 presented a possible aplicability as a screening marker of subjects with increased risk to develop leprosy, contributing indirectly for leprosy diagnosis.
Acesso aberto (Open Access)
Caracterização do padrão de expressão e metilação do gene P21CDKN1A/CIP1 em tumores mamários caninos
(Universidade Federal do Pará, 2018-04-20) SOUSA, Raissa Melo de; BORGES, Bárbara do Nascimento; http://lattes.cnpq.br/0676220027193876
The most of canine mammary tumors are malignant and associated with the animal death. One of the factors involved in this pathogenesis is the change in the expression level of the gene P21, which in turn encodes a protein that can inhibit tumor initiation and tumor progression. The methylation profile of gene can affect the cellular level of p21 and lead gene silencing or overexpression. Whereas the functional importance of the P21 gene, this study aimed to evalu-ate the methylation profile and expression in mammary tumors of dogs, in order to identify molecular markers of early diagnosis, survival and prognosis. Therefore, 83 tumor and non-tumor tissue samples were collected from dogs, undergoing surgery at the Veterinary Hospital "Mário Dias Teixeira”, in Belém -Pará. the DNA and RNA from each sample were submitted to extraction using a commercial kit. For the methylation analyzes, the obtained DNA was sub-mitted to the modification process, with a subsequent technique of Bisulfite Sequencing PCR, using region-specific primers and subsequent visualization in 2% agarose gel. The sequencing results were analyzed in BiQ Analyzer software in order to evaluate the methylation pattern. For gene expression analysis, the target gene mRNA was quantified using the real-time PCR technique using the GAPDH and HPRT1 genes as constitutive controls. Statistical data was performed using the Fisher Exact, Odds Ratio and Mann-Whitney tests in the GraphPad Prism program, considering the significant results when p ≤0.05, with a 95% confidence inter-val. In order to evaluate the methylation profile, the CpG islands of the P21 gene were characterized. The island 1 is located in an intron with 34 CGs, while an island 2 was identified in the exon, with 22 CGs. Both amplified generating a fragment of ~ 300bp. At island 1 no methylation was detected, whereas island 2 was methylated, but the island methylation profile was not different between the tumor, non-tumor and control samples. With these results was impossible compare the methylation values with clinical and expression data, suggesting that these regions are not altered. The expression levels of the tumor samples were low when compared to the non-tumor samples and control, with p (0.0001), show that the role of p21 in these tumors may be altered but not statistically significant when correlated with clinical histopathological data of patients. However, a reduced expression in the survival of animals> 1 year of age was observed, and a high expression in animals with survival <1 year of age, suggesting the influence of p21 as a marker of prognosis. More detailed studies of the P21 gene are still needed to see if these changes could be used as molecular markers, and thus aid on the prognosis and detection of cancer in the species.
Acesso aberto (Open Access)
Diagnóstico citológico e molecular da infecção pelo HPV em mulheres do município de Barcarena, Pará, Norte do Brasil
(Universidade Federal do Pará, 2010-06-02) NASCIMENTO, Ludmila Marcia Sousa do; BRITO JUNIOR, Lacy Cardoso de; http://lattes.cnpq.br/9705670940390281; SALGADO, Claudio Guedes; http://lattes.cnpq.br/2310734509396125
HPV (human papillomavirus) was appointed by the WHO (World Health Organization - WHO) as the main risk factor for developing cervical cancer, thus becoming an important and very serious public health problem, especially in underdeveloped countries or under development. The early sexual activity, multiple partners and casual sex, smoking, immunosuppression (eg, the population of AIDS patients), pregnancy, sexually transmitted diseases like herpes and chlamydia prior, in addition to non-compliance with the measures already taken to prevent Sexually Transmitted Diseases (STDs), such as the simple use of condoms is admittedly associated with the incidence of HPV infection. This research aimed to evaluate the diagnostic performance of the methodologies of conventional cytology (Pap test) compared to liquid based cytology, and to determine the prevalence of genotypes 16 and 18 of HPV in women without HPV cytopathic effect compatible with and relate to presence of inflammatory conditions, or not associated with HPV, with epidemiological data such as age, education, socio-cultural condition of women from the municipality of Barcarena - Pará - Brazil. To do so, in this study voluntarily, 50 women attended at the Health Unit Barcarena - Brazil, through the campaign to collect Pap test as a method of preventing cancer of the cervix. These women were informed about all procedures performed by the body of this health study and the results of this search and only after the volunteers have signed the Deed of Consent, they were included for sampling. The analysis and test results of liquid based cytology and conventional were performed according to the Bethesda Classification and reviewed blindly by two pathologists. For the analysis statistic was used Fisher's exact test and the "Screening Test" to determine the specificity / sensitivity of the methods, considering the significant value of p ≤ 0.05. Our results indicate that the use of liquid based cytology has demonstrated a number of advantages over conventional cytology. In molecular diagnostics (PCR) were observed occurrences of HPV types 16 and 18 in 10% of women attended. Among the cases that were PCR positive for types 16 and 16/18 most of the women were 27.4 years old on average, with more schooling, performing household chores and rural areas, and with instances of co-infection by infectious agents cause other sexually transmitted diseases. The results of this study reinforce the importance of maintaining free campaigns to prevent cervical cancer as a preventive measure in combating this disease, especially in Pará State, where, probably, the epidemiological profile of disease is associated with the large distances that women in river communities have to travel to perform this test free of charge, the type of economic activity in the region, the local bias still exists with the test, and the degree of difficulty of implementing effective return of patients to medical appointments after obtaining the test result and the same routing for molecular diagnosis of positive cases for type lesions ASC-H and CIN I, II and III.
Acesso aberto (Open Access)
Estudo da influência do uso de agrotóxicos e de polimorfismo do gene GSTT1 na etiologia de fissuras labiopalatais em pacientes do Estado do Pará
(Universidade Federal do Pará, 2014-08-28) MARTINS, Cláudia Maria da Rocha; BURBANO, Rommel Mario Rodriguéz; http://lattes.cnpq.br/4362051219348099
Birth defect or congenital malformation is any anatomic, metabolic or functional abnormality, inherited by a mechanism of Mendelian transmission or caused by a new mutation, a chromosomal alteration or physical aggression by an infectious, chemical or the fetus or embryo development . Its causes may be genetic or environmental, and, most often, are multifactorial origin, through the genetic predisposition factors interact with environmental factors triggers. In Pará state, a large number of individuals affected by Oral clefts are from rural areas, mainly in the northeastern state where it is notoriously indiscriminate use of pesticides harmful to human health, many of which have high potential teratogenic. The objective of our study was to investigate the association between the polymorphism (rs4630) in the GSTT1 gene and exposure to pesticides in etiology of oral clefts and analyze the pattern of changes in speech of patients according to the type of cleft. Eight three patients with cleft palate or lip, and of both sexes, and 83 mothers of these patients, all from the state of Pará, residing in rural and capital area were analyzed. Speech therapy and analyzes were performed with the blood of these individuals, the molecular analysis was performed. Statistical analysis was performed using the statistical software SPSS v.. 12.0 and BioEstat v. 5.0. Tests included testing multiple logistic regression test x2e the Fisher exact test. Our result consists of five different molecular analyzes. We found that the presence of the C allele in the genotype of the individual can influence the metabolism of xenobiotics and increase the risk to develop oral clift.
Acesso aberto (Open Access)
Inibição da atividade da Tirosinase por análogos do ácido Kójico
(Universidade Federal do Pará, 2014-11-14) CARDOSO, Erica de Tássia Carvalho; MAUÉS, Luis Antônio Loureiro; http://lattes.cnpq.br/4851018582496177; NASCIMENTO, José Luiz Martins do; http://lattes.cnpq.br/7216249286784978
Tyrosinase is an enzyme’s key for melanin biosynthesis. It is a "copper-dependent" enzyme which exhibits three intermediate states: deoxy (Cu1+ -Cu1+), oxi (Cu 2+ - O2 -Cu2+) e met (Cu2+) - Cu2+). This enzyme has bifunctional activity since it can oxidize phenol or catechols in their corresponding o-diphenols. In addition, oxidation of phenols can be described by Michaelis-Menten kinetics. Hyperpigmentation disorders and enzymatic browning of fruit and fungi is associated with tyrosinase.Therefore the research for substances of natural or synthetic origin that could have an effective regulation on the behavior of this enzyme is a key factor of the treatment of such disorders. In this perspective, the present study consisted in analyze the biochemically anti-tyrosinase activity of kojic acid and its analogues derivatives from 4H-pyrones (S-01, S-02, S-03 and S-04) and derivatives from diidropirano [3, 2-b] cromenodionas (S-05, S-06, S-07 and S-08) chemically designed by molecular modeling in LPDF from ICEN UFPa. The kinetics of substances S-02, S-04, S-06, S-07 and S-08 showed competitive inhibition, similar to the pattern of inhibition of kojic acid with Ki values = 145,0 ± 20,0 μM; 64,0 ± 10,0 μM; 4,0 ± 0,0 μM; 6,0 ± 0,0 μM; 9,0 ± 0,0 μM, respectively, and 5,0 ± 0.0 μM for kojic acid, while S-01 had mixed type of inhibition (Ki = 999,0 ± 150,0 μM). Since the S-03 and S-05 substances showed no inhibitory activity. The substances tested demonstrated a high degree of safety both in the integrity of the erythrocyte membrane in the hemolysis test as in the test with MTT viability in cultures of MRC5 fibroblasts, culture of nerve cells from chicken embryo retina and B16F10 melanoma. Thus, it was demonstrated that S-02, S-04, S-06, S-07 and S-08 substances have potent activity as inhibitors of tyrosinase and may be candidates for the treatment of pigmentation disorders.

Navegar

Navegando Dissertações em Neurociências e Biologia Celular (Mestrado) - PPGNBC/ICB por CNPq "CNPQ::CIENCIAS BIOLOGICAS::BIOQUIMICA::BIOLOGIA MOLECULAR"