Teses em Neurociências e Biologia Celular (Doutorado) - PPGNBC/ICB

URI Permanente para esta coleçãohttps://repositorio.ufpa.br/handle/2011/2390

O Doutorado 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).

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Análise de patógenos orais entre indivíduos portadores de câncer gástrico e indivíduos sem câncer
(Universidade Federal do Pará, 2021-06) OLIVEIRA, Gyselle Ribeiro de Carvalho; BURBANO, Rommel Mario Rodriguéz; http://lattes.cnpq.br/4362051219348099; https://orcid.org/0000-0002-4872-234X
The loss of teeth and lack of oral hygiene have been associated with the risk of developing gastric cancer in several populations evidenced in epidemiological studies. In this study, we quantitatively compared the proportion of oral pathogens in individuals with gastric cancer and individuals without cancer in a referral hospital in the city of Belém, Brazil. This study evaluated 192 patients with gastric cancer and 192 patients without cancer. Periodontal clinical examination was performed, and all individuals were submitted to the collection of salivary and dental biofilms. When comparing the median periodontal indexesin the gastric and cancer-free groups, it was statistically significant in the gastric cancer group compared to the probing depth of the periodontal pocket. Levels of bacterial DNA were observed in saliva and dental plaque, with a statistically significant difference between individuals with cancer and without neoplasia in all the bacteria surveyed. Significant relationships between biological agents and gastric cancer have been found in bacterial species that cause high rates of periodontal pathology and caries. The results suggest a different quantitative association in the presence of oral pathogens between individuals without cancer and patients with gastric cancer. As noted, it cannot be said that the bacteria present in the oral cavity increase the risk of gastric cancer or are aggravating factors of the disease. However, it is worth mentioning that, as it is part of the digestive system, the lack of care for the oral cavity can negatively affect the treatment of patients with gastric cancer.
Acesso aberto (Open Access)
Análise de variações genômicas em genes da região cromossômica 22q11.2 em pacientes esquizofrênicos do Estado do Pará
(Universidade Federal do Pará, 2015-08-29) MORAES, Leopoldo Silva de; BURBANO, Rommel Mario Rodriguéz; http://lattes.cnpq.br/4362051219348099
The COMT Val158Met and ZDHHC8 rs175174 polymorphisms have received increased attention in the molecular study of schizophrenia not only because they are localised to the main susceptibility locus of the disease, 22q11, but also because they are related to the dopaminergic status of the prefrontal cortex and the activity of several neuronal proteins, respectively. To evaluate the influence of the polymorphic genotypes on schizophrenia, we used real-time PCR to genotype 130 patients and 175 controls in a population from the North Region of Brazil. Our results indicated an absence of association between both polymorphisms and the likelihood of schizophrenia in the population studied. However, when categorised by gender, we found a dichotomous association between the Met/Met genotype of the COMT Val158Met polymorphism and susceptibility to schizophrenia, conferring a higher probability of disease in men (OR = 10.76; CI 95% = 2.09–55.34; p = 0.004) than in women (OR = 0.23; CI 95% = 0.07–0.69; p =0.009). Moreover, the variance analysis showed an association of the genotypes Val/Met (COMT Val158Met) and GG (ZDHHC8 rs175174) with higher average age at onset of schizophrenia. Our study supports the hypothesis of a gender-dependent association of the COMT Val158Met polymorphism with schizophrenia, in addition to suggesting an influence of both polymorphisms studied on the age at disease onset.
Acesso aberto (Open Access)
Avaliação de polimorfismos de genes metabolizadores de xenobióticos em pacientes com fissura labiopalatina atendidos no Estado do Pará
(Universidade Federal do Pará, 2013) KHAYAT, Bruna Cláudia Meireles; BURBANO, Rommel Mario Rodriguéz; http://lattes.cnpq.br/4362051219348099
Orofacial cleft palate or lip is one of the most common birth defects and several existing studies that relate to multifactorial causes malformation. Among the various environmental causes are the ethyl and maternal smoking habits, as well as the use of pesticides. The response of human embryo teratogenic agents is well known. However, it is known that different organisms metabolize differently the same chemical component, this is due to intrinsic genetic characteristics related to different enzymatic runs. Such differences can be investigated from the analysis of polymorphisms in genes related to metabolism of these xenobiotics, which may well be related to etiogênese palatine cleft lip. The objective of our study was to analyze polymorphisms in seven genes, PON1 ( rs662), PON1 ( rs854560 ), MTHFD1, CYP2E1, EPHX1, ABCB1, AHR, where a correlative analysis with environmental factors such as exposure to pesticides was performed in order to assess whether there is influence of different polymorphic variants and environmental interactions in such etiogênese of cleft Lip and Palate. The total number of samples analyzed were 166 subjects, 83 patients affected by cleft, with an average age of 7 years (SD 5 years) and 83 mothers of the same. In our samples, the males was 64 % of the total affected. A plug for the collection of epidemiological data was developed for the study, the biological material collected for analysis was blood. Statistical analysis was performed using the BioStat 5.3, SPSS 12.0 software and plink 1:07. Our result is four different analyzes for each polymorphism. Initially, we observed differences between genotypic frequencies found in affected and mothers of these populations and those of healthy individuals. This aimed to find differences among genotypes that may justify the genesis of FLP, after exposure of mothers and intrauterinamente of the children to pesticides. Secondly, we looked at whether there were differences between the affected and maternal genotypes, which could represent significant differences between these two groups of individuals (as the mothers, regardless of exposure to pesticides could have FLP if the genotype was of high importance) and which may be related to the FLP. In a third analysis, we observed that the genotypes found in individuals with FLP, are related to the reported pesticide exposure as an etiological factor of these malformations. Ultimately, we aim, through regression analysis to determine whether the genotypic characteristics of these targets of study, may have influenced the phenotype of the type of cleft, lip only be either palate or cleft lip. The distribution of types of cracks between affected was 12% only for chapped lips, only 19% to 69% palate and the cracks in our sample group reached the lip and palate.
Acesso aberto (Open Access)
Avaliação in vitro dos possíveis efeitos citotóxicos, genotóxicos e mutagênicos das drogas antimaláricas artemisinina e artemeter em linfócitos humanos
(Universidade Federal do Pará, 2012-05-25) CARDOSO, Plínio Cerqueira dos Santos; BAHIA, Marcelo de Oliveira; http://lattes.cnpq.br/3219037174956649; BURBANO, Rommel Mario Rodriguéz; http://lattes.cnpq.br/4362051219348099
Artemisinin is a substance extracted from the Chinese plant Artemisia annua L., and widely used in natural medicine for a treatment of various diseases. Artemether is a substance synthesized from artemisinin. These drugs belong to a special group of molecules called sesquiterpene lactones widely administered in the treatment of malaria. Although considered effective anti-malarial drugs, very little is known about the genotoxic and cytotoxic effects of these drugs. Therefore, in the present study, we evaluated the genotoxic, mutagenic and cytotoxic effects of artemisinin and artemether in cultured human lymphocytes using the comet assay, the micronucleus test and a cytotoxicity assay for detection of necrosis and apoptosis by fluorescent differential acridine orange/ethidium bromide (LA/BE), respectively. Our results showed a significant increase (p<0.05) in the rate of DNA damage measured by comet assay and in the micronucleus frequency after treatment with both drugs. It was also observed that only artemisinin induced a statistically significant increase (p<0.05) in the number of lymphocytes with death by necrosis 48 h after treatment. Thus, it was shown in our work that these two drugs exert mutagenic, genotoxic and cytotoxic effects in cultured human lymphocytes under the conditions evaluated. Our data indicate the need for caution in the use of such drugs, since genotoxic/mutagenic effects may increase the risk of carcinogenesis.
Acesso aberto (Open Access)
Avaliação in vivo do potencial efeito protetor da prolactina contra danos causados pelo metilmercúrio
(Universidade Federal do Pará, 2022-04) CUNHA, Lorena Araújo da; ROCHA, Carlos Alberto Machado da; http://lattes.cnpq.br/5789536737681588; BURBANO, Rommel Mario Rodriguéz; http://lattes.cnpq.br/4362051219348099; https://orcid.org/0000-0002-4872-234X
Biodegradable metals, such as mercury, accumulate in living organisms throughout their lives (bioaccumulation) and also in food webs (biomagnification), and can reach high concentrations in humans. Human contamination by mercury found in drinking water and food can be common, especially in riverine communities that depend on fish as their main source of protein. In vitro studies with human cell lines exposed to methylmercury showed that prolactin has cytoprotective properties against cytotoxic and mutagenic effects of this metal, and can act as a co-mitogenic factor and apoptosis inhibitor. The present study investigated, in vivo, the protective potential of prolactin against the toxic effects of methylmercury in mammals, using the mouse (Mus musculus) as a model. Biomarkers of genotoxicity (comet assay and micronucleus test) and oxidative stress (lipid peroxidation and activity of CAT and SOD enzymes), together with histological (in liver, kidney and brain tissue samples) and biochemical (renal and hepatic and measurement of Hg and PRL in the blood), were used to verify the protective potential of prolactin in mice exposed to methylmercury. It was observed, in a more expressive way, a reduction in the alterations of the renal and hepatic biochemical parameters and of the mutagenic effects in the presence of prolactin, in comparison with the isolated effects of the metal. When prolactin was used together with the metal, a decrease in histological damage and an increase in SOD enzyme activity were also observed. The study results indicate that prolactin has protective effects against toxic impacts of methylmercury.
Acesso aberto (Open Access)
Estudo do papel das proteínas LYN, CKB e SRC na carcinogênese gástrica
(Universidade Federal do Pará, 2015-04-28) MELLO, Adriano Azevedo de; BURBANO, Rommel Mario Rodriguéz; http://lattes.cnpq.br/4362051219348099
Gastric cancer (GC) is the fourth most frequent cancer type and the second ighest cause of câncer mortality worldwide. A better understanding of the biology of the progression of this neoplasia is crucial to reducing the mortality rate with the development of novel patient management and therapeutic strategies. In this study, we analyzed gastric cancer samples and found elevated expression of SRC and LYN kinase mRNA and protein but decreased levels of CKB kinase, alterations that may have a role in the invasiveness and metastasis of gastric tumors. Expression of the three studied kinases was also associated with MYC oncogene expression, a possible biomarker for gastric cancer. To understand the mechanisms that regulate the expression of these genes, we evaluated the DNA methylation patterns of the three kinases. We found that SRC and LYN hypomethylation and CKB hypermethylation were only present in neoplastic gastric samples. The loss of SRC and LYN methylation was associated with increased levels of mRNA and protein expression, suggesting that DNA methylation is involved in regulating the expression of these kinases. The frequency of hypermethylation and partial methylation of CKB was higher in the gastric cancer samples than in the non-neoplastic gastric samples; however, CKB expression was found to be only partly regulated by DNA methylation. In an analysis of the expression data, we found that alterations in the DNA methylation pattern of the three studied kinases were also associated with advanced gastric cancer, deeper tumor invasion and the presence of metastasis. Therefore, SRC, LYN and CKB expression or DNA methylation could be useful markers for predicting tumor progression and targeting in anti-cancer strategies.
Acesso aberto (Open Access)
O impacto da implantação do teste NAT-HBV na Fundação Centro de Hemoterapia e Hematologia do Estado do Pará (HEMOPA), Região Norte do Brasil
(Universidade Federal do Pará, 2019-03-21) CORRÊA, Angelita Silva de Miranda; BURBANO, Rommel Mario Rodriguéz; http://lattes.cnpq.br/4362051219348099
Nucleic acid testing (NAT) for virus detection during blood screening has helped to prevent transfusion-transmitted infections worldwide. In northern Brazil, NAT was implemented in 2012 for HIV and HCV and more recently, in January 2015, the screening for HBV was included and currently used concomitant with serological tests (HBsAg and anti-HBc). This study aims to evaluate the prevalence and the incidence of HBV infection among voluntary blood donors at ten regional blood centers of HEMOPA Foundation in Pará state and to compare the residual risk of transfusion-transmitted HBV infection before and after the Brazilian HBV-NAT implementation. The prevalence (restricted to FT donors) and incidence (restricted to RP donors) of HBV were calculated based on rates of confirmed positive samples. Residual risk was based on the incidence and WP model described by Schreiber and coauthors. Logistic and Poisson regression were used in the statistical analysis by SPSS v20.0. A p value <0.05 was considered statistically significant. HBV prevalence in the periods before and after the implementation of HBV-NAT were 247 and 251 per 100,000 donations, respectively. Seroconversion rates were 114 and 122 per 100,000 donations in the two periods, respectively. The residual risk (RR) for HBV decreased significantly in the period after the implementation of HBV-NAT, with a reduction of 1: 144.92 to 1: 294.11 donations (p <0.001), significantly increasing transfusion safety at HEMOP Foundation, in the Northern Region of Brazil.
Acesso aberto (Open Access)
Investigação de efeitos mutagênicos em trabalhadores expostos à radiação ionizante no Brasil
(Universidade Federal do Pará, 2015-12-18) CUNHA JUNIOR, Luiz Raimundo Campos da Silva e; BURBANO, Rommel Mario Rodriguéz; http://lattes.cnpq.br/4362051219348099
Ionizing radiation (IR) are present in most of the early diagnosis of a multitude of diseases, many cancers are included, and have the characteristic of a quick and accurate diagnosis, and often cheaper. The use of this type of energy but requires specific care protection, since the IR has a characteristic of altering the genetic material through mutations. The radiology area operators in hospitals are the class of workers who are exposed more directly and thus are targets of investigations that may assist in understanding the interaction of IR with the biological material, in addition to assisting these professionals in requirement radiological protection. We collected 73 samples of individuals working in various radiology departments in five hospitals in four different states in Brazil (São Paulo, Minas Gerais, Rio Grande do Sul and Pará). The selection criteria for participation were: at least 18 years old and 2 years in the profession, not alcoholic or smoker, not taking drugs. For cytogenetic analysis were performed the comet test and micronucleus, and chromosome aberration study. This study was approved by ethics committee. All the samples were compared to individuals of the same age and gender who have not gone through any kind of radiological examination in the last 6 meses.Quando compared with the control, MN tests and AC showed a total damage, using the t test, the database and SPSS BioEstat. The comet assay showed a higher level of damage compared to controls (0.84 0,47). The average age was established and made relationship between gender and age of the participants, the more damage levels in females compared to males. Individuals aged over 45 years also showed a higher level of damage when compared with the age. A factor to be taken into consideration is that the population of Porto Alegre present a lower level of damage compared to other groups, and most likely this event due to the use of DR equipment Direct conversion. The Belo Horizonte and Ribeirão Preto equipment using CR and Belém, conventional.
Acesso aberto (Open Access)
Modelo experimental de imunossupressão com ciclofosfamida em Rattus norvegicus da linhagem wistar e primatas não humanos da especie Cebus apella: análise genotoxicológica
(Universidade Federal do Pará, 2011-12-23) SOUZA, Patrícia Carvalho de; BURBANO, Rommel Mario Rodriguéz; http://lattes.cnpq.br/4362051219348099
We established a model of immunosuppression in rats by inoculation of the alkylating agent Cyclophosphamide (CY). The administration of 50 mg/kg CY in Wistar rats caused a significant decrease in the parameters of cellularity, and relative weight of lymphoid organs. For analysis of antibody titre of the test on the plaque forming cells and hemolysis test was proven that the humoral immunity of rodents suffered suppression. Four inoculations were carried out and this immunosuppressive intervals between inoculations was determined by recovery of normal levels of the aforementioned parameters. The change in differential counts of white blood cells represented the greatest adverse effect of CY, observed in laboratory parameters analyzed in Cebus apella. Both times it was administered the drug decreased the number of lymphocytes and neutrophils subsequently decreased, but only in the second was observed immunosuppression. Since the phylogenetic proximity of nonhuman primates, this experimental design is of paramount importance for the study of tumors at various stages of development and mainly for testing new drugs and therapeutic regimens. With respect to genotoxicity analysis of CY can conclude that in Wistar rats, the administration of CY significantly increased frequency of micronuclei in polychromatic erythrocytes (MN ECPs) and caused a cytotoxic effect (P <0.05). In C. apella, the peripheral blood lymphocytes after treatment with CY showed a significant increase in media MN/1000 lymphocyte cells compared to control (P <0.05). The concentration of 50mg/kg of CY in C. apella, LD50 is the concentration of the drug, whereas 50% of these animals died during the trial of immunosuppression. Until the development of this work, do not know the concentration corresponding to the LD50 in this species. In comparing the two species of animals used in this work, non-human primates have a more rapid immune recovery compared to rats. Probably the ability to metabolize the drug is more effective in C. apella. Our results support, therefore, that non-human primates are the best experimental models due to its great evolutionary and phylogenetic proximity to humans.
Acesso aberto (Open Access)
Papilloma vírus humano: prevalência, distribuição e importância como fator preditivo para metástases linfonodais em carcinoma do pênis
(Universidade Federal do Pará, 2013-07-09) FONSECA, Aluizio Gonçalves da; BURBANO, Rommel Mario Rodriguéz; http://lattes.cnpq.br/4362051219348099
The etiology of squamous cell carcinoma of the penis (CEP) is related to multiple risk factors such as the presence of foreskin, poor hygiene, chronic dermatitis and smoking. However, the risk factor most extensively studied, is infection by human papilloma virus (HPV). It is well established that this plays an important etiologic role in cancers of the uterine cervix, however, its association with CEP has been the focus of debate, demonstrating viral presence ranging from 15% to 80% of cases, suggesting that only a subset of these tumors is caused by HPV. The prognosis is negatively influenced mainly by the presence of metastases in inguinal lymph nodes. Thus, the surgical aproach of them, is of vital importance in curing the disease. On the other hand, the available methods for staging these nodes are imprecise and lymphadenectomy are accompanied by significant morbidity. A description of other histological markers is scarce because of the rarity of these tumors. The objective of this study is to evaluate the prevalence, distribution and association between HPV and histological parameters of poor prognosis, in order to determine their possible predictive value for inguinal metastases, as well as prognostic factors already described. Paraffin tumor specimens from 82 patients with squamous cell carcinoma of the penis were tested for prevalence and genotype distribution of HPV by PCR. The HPV status was correlated with histopathological factors and metastatic inguinal. It was also evaluated the influence of various histological tumor factors, in lymphonodal disease free survival at 5 years. Follow-up ranged from 1 to 71 months (mean 20 months). HPV DNA was detected in 60.9% of the sample having the most prevalent viral type 11 and 6 (64% and 32%, respectively). There was no significant correlation independent of the histological variables of poor prognosis with HPV status. The probability of lymphonodal disease free survival at 5 years, was not affected by HPV (log rank test = 0.45). The only independent factors for pathological inguinal metastases were T stage ≥ T1b-T4 (p = 0.02), lymphovascular invasion (p = 0.04) and infiltrative invasive front (p=0, 03). The status and distribution of HPV showed no correlation with histological factors of poor prognosis, nor showed significance in predicting lymph node metastases in CEP.
Acesso aberto (Open Access)
Perfil de expressão diferencial de microRNAs durante o armazenamento prolongado de concentrados de plaquetas em banco de sangue
(Universidade Federal do Pará, 2019-02-28) MAUÉS, Jersey Heitor da Silva; BURBANO, Rommel Mario Rodriguéz; http://lattes.cnpq.br/4362051219348099
Platelet concentrate (PC) is a key blood component, which even in good storage conditions, susceptible to cellular damage over time. Hence, blood banks discard unused PC bags after 5 days of storage. Biomarkers of PC quality are therefore highly sought after in blood bank governance. We used the data (Gene Expression Omnibus: GSE61856) generated with next-generation sequencing to examine the expression profiles of microRNAs (miRNAs) from PCs that were stored for 6 days in a blood bank, that is, 1 day longer than is normally stored PC. We identified the 14 most differentially expressed miRNAs by comparing a control PC on the first day of storage with the PCs on each of the subsequent 5 days of storage from day 1 to 6. In all, we identified nine miRNAs with the downregulated profile (miR-145-5p, miR-150-5p, miR-183-5p, miR-26a-5p, miR-331-3p, miR-338-5p, miR-451a, miR-501-3p, and miR-99b-5p) and five upregulated miRNAs (miR-1304-3p, miR-411-5p, miR-432-5p, miR-668-3p, and miR-939-5p). These miRNAs were validated by real-time quantitative PCR in 100 PC units. As each PC unit is composed of platelets of five individuals, the validation was thus performed in 500 individuals (250 men and 250 women, comprised 18–40 years old adults). The data were analyzed with hierarchical clustering and principal component analysis, which revealed the variation of mean relative expression and the instability of miRNAs half-life on the fourth day of PC storage, which coincides with time of onset of platelet storage lesions. These new observations can usefully inform future decision-making and governance in blood banks concerning PC quality.
Acesso aberto (Open Access)
Prevalência e associação da infecção por Helicobacter pylori e do vírus de Epstein-Barr em adenocarcinoma gástrico, em uma população do norte do Brasil
(Universidade Federal do Pará, 2012-12-13) FERRAZ, Jefferson José Sodré; QUARESMA, Juarez Antônio Simões; http://lattes.cnpq.br/3350166863853054; BURBANO, Rommel Mario Rodriguéz; http://lattes.cnpq.br/4362051219348099
Gastric neoplasias are the second leading cause of cancer-related deaths and although discoveries over physio-pathology of tumour cells, cancer is considered, to the best of our knowledge, minimally controlled by modern medicine. Gastric carcinoma is among the few malignant neoplasms in which infectious agents play an important role. The aim of the present work was to research the prevalence and the association of Helicobacter pylori and Epstein-Barr virus infection in gastric adenocarcinoma in a northern population of Brazil. A hundred twenty-five samples of gastric adenocarcinoma were analyzed by PCR to detect H. pylori and pathogenic genotype H. pylori-cagA+, by in situ hybridization to detect EBV, and by histopathological analysis to determine epidemiologic and clinico-pathological data. It was observed a higher frequency in male patients (68%) as much as older patients (78%). Prevalence to H. pylori was 88%, and it was considered high when compared to early studies in northern region of Brasil. To EBV the prevalence was 9,6%. Patients H. pylori-cagA+ showed increased relative risk to intestinal type adenocarcinoma. The case’s frequency to III and IV stages of the disease was 82,4%, demonstrating that the diagnostic to this neoplasia has been done late. The urease positive cases presented a higher than four-fold relative risk (OR=4,231) to H. pylori-cagA+, the more pathogenic genotype. There wasn’t statistical significance to the association between H. pylori and EBV in the studied population; however the EBV positive cases showed 100% positivity to H. pylori suggesting a possible synergistic relation of these agents in gastric carcinogenesis.

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