Programa de Pós-Graduação em Neurociências e Biologia Celular - PPGNBC/ICB
URI Permanente desta comunidadehttps://repositorio.ufpa.br/handle/2011/2374
O Programa de Pós-Graduação em Neurociências e Biologia Celular (PPGNBC) é parte integrante do Instituto de Ciências Biológicas (ICB) da Universidade Federal do Pará (UFPA), sendo constituído por: Mestrado e Doutorado em Neurociências e Biologia Celular, com área de concentração em Neurociências ou Biologia Celular.
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Item Acesso aberto (Open Access) 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/0000-0002-4872-234XThe 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.Item Acesso aberto (Open Access) Atividade e expressão da metaloprotease GP63 nas espécies Leishmania (Leishmania) amazonensis e Leishmania (Viannia) brasiliensis(Universidade Federal do Pará, 2021-06) SOARES, Dara da Costa; SILVA, Edilene Oliveira da; http://lattes.cnpq.br/7410116802190343; https://orcid.org/0000-0001-6555-6868The american cutaneous leishmaniasis (ATL) is a neglected tropical disease caused by protozoa of the genus Leishmania sp. In Brazil, Leishmania (L.) amazonensis and Leishmania (V.) braziliensis are the main pathogenic species. The different strains and species, as well as the immune response of the vertebrate host, are key points in the development of the disease and, consequently, in the different clinical manifestations caused by these protozoa such as localized cutaneous leishmaniasis (LCL), diffuse cutaneous leishmaniasis (LCD) and mucocutaneous leishmaniasis (CML). Leishmania parasites have improved mechanisms with the ability to silence the microbicidal response of infected macrophages through the action of virulence factors such as glycoprotein 63 (GP63). This glycoprotein, which has a zinc- dependent catalytic site, is the main surface metalloprotease of Leishmania and is able to modulate the vertebrate host's immune response by cleaving a wide set of cytosolic substrates. However, due to the need to understand the role and involvement of GP63 in infection processes and different clinical manifestations, it is important to analyze how this molecule is present during these processes. In view of this, the hypothesis of this study is whether there is a difference in the expression of the virulence factor GP63 between two ATL-causing species, Leishmania (Leishmania) amazonensis and Leishmania (Viannia) braziliensis, which cause different clinical manifestations. Therefore, the objective of this work was to analyze the expression and activity of GP63 in the species Leishmania (L.) amazonensis and Leishmania (V.) braziliensis, which are more relevant to the involvement of ATL. The activity of GP63 was analyzed using promastigote forms in the stationary phase (7 days of culture) and they were submitted to analysis of the proteolytic profile through DQ-gelatin (10μg / ml) in fluorimeter (VICTOR Multilabel Plate Reader X) with wavelength of 480-520 nm and by zymography gel containing 0.1% gelatin as substrate. The expression of GP63 was analyzed by Western blot using anti-GP63 antibody. The immunostaining and quantification of the GP63 protein were analyzed by indirect immunofluorescence. This work showed for the first time that the species Leishmania (L.) amazonensis shows greater expression of the glycoprotein 63 kDa compared to the species Leishmania (V.) braziliensis. The greater expression of this protease was also accompanied by an increase in gelatinolytic activity in the analyzed species. These results allow suggesting a correlation in the involvement of this virulence factor between the clinical manifestations that are caused by these two species analyzed in this work.Item Acesso aberto (Open Access) Impacto da busca ativa especializada no diagnóstico da hanseníase: avaliação longitudinal e comparativa de aspectos clínicos e laboratoriais em áreas endêmicas no Pará e no Maranhão(Universidade Federal do Pará, 2024-08) COSTA, Izabelle Laissa Viana; COSTA, Patrícia Fagundes; http://lattes.cnpq.br/6487407290759330; SALGADO, Claudio Guedes; http://lattes.cnpq.br/2310734509396125Leprosy is a disease that represents a significant public health problem in various parts of the world, including Brazil. To improve epidemiological data, active case finding activities and longitudinal research represent a transformative approach to disease control. In this context, the present study aimed to evaluate and compare the clinical and laboratory aspects of patients with leprosy, their contacts, and schoolchildren over a one-year period in endemic areas in Pará and Maranhão. To achieve this, a longitudinal study was conducted, characterized by active case finding activities in Imperatriz-MA, São Luís-MA, and Marituba-PA, where registered leprosy cases in the Notifiable Diseases Information System (SINAN), their contacts, and school-aged children were evaluated. Participants underwent neurodermatological evaluation and blood collection for the titration of IgM anti-PGL-I antibodies, as well as intradermal scraping of the earlobes and elbows for bacilloscopy and qPCR. After one year, in 2023, participants from the municipalities of Imperatriz and São Luís were re-evaluated, and new participants were included. Among 522 individuals included in this study, 135/522 (25.9%) were clinically and/or laboratorially re-evaluated in 2023, and 387/522 (74.1%) were evaluated exclusively in 2022 or 2023. In 2022, new cases were identified among 66/221 (29.9%) contacts and 23/195 (11.8%) schoolchildren. Additionally, 9/34 (26.5%) relapses and 2/34 (5.9%) patients with therapeutic insufficiency or failure were diagnosed among index cases. In 2023, new cases were observed among 70/126 (55.5%) contacts and 10/29 (34.4%) schoolchildren. Furthermore, 7/12 (58.3%) relapses and 1/12 (8.3%) patients with therapeutic insufficiency or failure were diagnosed among index cases. In the neurodermatological evaluation, among schoolchildren and contacts who were re-evaluated, individuals with an altered superficial fibular nerve were found to be 4.3 times more likely to be in the disease case group (p < 0.05; 95% CI = 1.58- 12.74; OR = 4.32). The bacilloscopy test identified the etiological agent in 7/222 evaluated individuals (3.1%), with 4/7 (57.1%) being among individuals with a prior diagnosis of leprosy. Regarding the serological analysis of re-evaluated individuals, seropositivity was observed in 26/106 (24.5%) individuals in 2022, and 7/106 (6.6%) in 2023, a statistically significant decrease (p < 0.05). A high positivity rate for the qPCR technique was observed, including 9/10 (90%) relapses, 55/88 (62.8%) new cases, and 43/151 (48.3%) contacts. These data highlight a concerning scenario characterized by a high number of hidden leprosy cases in the analyzed regions, and a significant increase in diagnosis rates after one year of follow-up in the communities, underscoring the importance of longitudinal research and the implementation of different diagnostic and monitoring techniques for a better understanding of leprosy and its outcomes in endemic areas.Item Acesso aberto (Open Access) Significado da expressão de p16INK4A e da perda de heterozigosidade do gene PTEN no carcinoma epidermóide bucal relacionado ao papilomavírus humano(Universidade Federal do Pará, 2023-06) KATO, Valdenira de Jesus Oliveira; ALCÂNTARA, Diego Di Felipe Ávila; http://lattes.cnpq.br/1794240697748468; https://orcid.org/0000-0001-5045-2265; BURBANO, Rommel Mario Rodríguez; http://lattes.cnpq.br/4362051219348099; https://orcid.org/0000-0002-4872-234XThe p16 and PTEN genes are part of the family of tumor suppressor genes commonly associated with the inactivation of a variety of human cancers. The loss of its expression has been studied worldwide in oral squamous cell carcinoma (OSCC). In this study, we evaluated the hypothesis that p16 cooperates with inactive PTEN during OSCC pathogenesis, especially in tumor aggressiveness and proliferation. For that, 119 OSCC samples were used in which the relationship between HPV infection, p16 expression and PTEN mutations were evaluated throug himmunohistochemistry (IHC), western blot, immunofluorescence and sequencing techniques. The results of this study demonstrated that PTEN has high positivity in patients with more advanced tumor size (p < 0.01) and lymph node metastasis (p = 0.02). Statistical analysis showed that p16 expression was strongly associated with the presence of HPV (p<0.0001), but that its aberrant expression is not related to altered PTEN (p=0.52). It was also observed that 60% of the samples in stage IV (advanced stage of the tumor) were statistically associated with the presence of mutation. It is concluded that PTEN and p16 are suppressor genes that control tumor progression. In the current study, PTEN showed great erreactivity in advanced stages of the disease (greater than seven times). p16 was strongly associated with HPV, but did not show a significant association with any clinical-pathological factor analyzed. Both proteins are of great importance in the prognosis of patients. Viral presence has been shown to decrease tumor aggressiveness. Lesions in advanced stages have a shorter survival, in addition, the presence of mutation was more commonly observed in advanced stages of the disease. It was observed that smoking patients witht he absenceof p16 are significantly associated with a survival rate twice as low.