Navegando por CNPq "CNPQ::CIENCIAS BIOLOGICAS::IMUNOLOGIA"

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Ação do alcaloide (+)-filantidina sobre o protozoário Leishmania (Leishmania) amazonensis e a célula hospedeira
(Universidade Federal do Pará, 2014-08-14) MORAES, Lienne Silveira de; SILVA, Edilene Oliveira da; http://lattes.cnpq.br/7410116802190343
Leishmaniasis is an antropozoonotic disease caused by parasites of the genus Leishmania. These parasites proliferate primarily within macrophages of mammals and are responsible for promoting a variety of clinical manifestations, such as cutaneous leishmaniasis (CL) and mucocutaneous leishmaniasis (MCL). The treatment available is chemotherapy, but is limited by toxicity and requires a long term treatment. The study of natural products from plants such as antileishmanial agent currently plays an important role in the search for new drugs for the treatment of leishmaniasis. (+)-phylantidine, is an alkaloid extracted from stem of Margaritaria nobilis of the family Phyllanthaceae. The aim of this study is evaluated the effects of (+)-phylantidine on promastigotes forms of Leishmania (Leishmania) amazonensis and host cell. Antiproliferative activity of promastigotes forms was observed when parasites were treated with 50, 100 e 200 μg/mL of alkaloid for 96 hours, with reduction of 73.75%, 82.50% and 88.75%, respectively when compared with non-treated parasites. In the period of 96 hours it was observed an IC50 of 56.34 μg/mL. Amphotericin B was used as reference drug and reduction of 100% in parasites treated with 0.1 μg/mL was observed after 96 hours. Treatment with the alkaloid promoted important changes in promastigotes that were observed by scanning and transmission electron microscopy. Alterations in cell body, flagellum, kinetoplast, mitochondria, rosette formation, presence of electrodense vesicles suggestive of lipid body and increase in structures like acidocalcisssomes were observed. In the host cell no cytotoxic effect was observed in the macrophages treated with the alkaloid and analysis by scanning electron microscopy showed that the alkaloid promoted an increase in the number of cytoplasmic projections, increased cell volume and spreading. Thus, these results demonstrate that (+)-phylantidine was effective in reducing the growth of the protozoa, without citotoxy effect which may represent a promising natural alternative source for the treatment of leishmaniasis.
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Análise imunológica e genotóxica em Rattus Novergicus da linhagem wistar tratados com ciclofosfamida
(Universidade Federal do Pará, 2016-08-11) CARVALHO, Heleniana Maria Miranda de; BURBANO, Rommel Mario Rodriguéz; http://lattes.cnpq.br/4362051219348099
The development of this work has given up due to the need to better understand the immune system, taking into account the diversity of experimental immunosuppression models as well as the variety of immunological responses and genotoxic differences these, related species, the drug and doses used. Thus, aim of this study was to analyze the effects on the immune system and genotoxic effects in Rattus norvegicus Wistar, after inoculation of the alkylating agent cyclophosphamide (CY). The administration of 50 mg / kg in rodents CY, possible to observe a significant decrease in the parameters of cellularity and relative weight of lymphoid organs. The humoral immunity of rodents has undergone deletion, since the analysis of the antibody titration was performed on the test plate forming cells and hemolysis testing. four inoculations that immunosuppressant and the intervals between the inoculations was determined by recovery of normal levels of the above parameters were performed. Both times the drug was administered, there was a reduction in the number of lymphocytes and neutrophils subsequently decreased, but only the second contact CY was observed immunosuppression. The analysis of the genotoxicity of cyclophosphamide (CY) was analyzed using the comet assay and was of paramount importance because dectamos genomic damage occurring in DNA exposed to different doses of cyclophosphamide (CY), which were 50 mg / kg in the first two phases and 25 mg / kg during the last two phases of the experiment. Furthermore, it was found that the genotoxic effects are cumulative with each CY dose applied, because even being administered in the third phase, the middle concentration (25 mg / kg) of the two inoculations initial CY the damage index does not correspond to half damage indices of the first and second vaccination. However, the analysis and immunologically genotoxicamente rodents, our work will enable testing new therapeutic immunosuppression regimens.
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Avaliação da resposta imunológica a vacina da Hepatite B nos trabalhadores do Hospital Municipal de Imperatriz-MA
(Universidade Federal do Pará, 2012) SANTOS, Wllington Jorge dos; MARTINS, Luisa Caricio; http://lattes.cnpq.br/1799493244439769
The hospital offers risk when the exposure of health professionals and other workers to a variety of materials, especially organic. This study aims to determine the prevalence of serological markers for HBV (ABsAg, anti-HBc and anti-HBS) and analyze the immune response to hepatitis B vaccine among workers of the Municipal Hospital Imperatriz- MA. We consulted the medical records of 257 hospital workers in different categories of professionals. Was removed from the records information about the immunization schedule for hepatitis B, and the results of serological markers (HBsAg, Anti HBs, Anti HBC total) performed by them in 2010 and 2011. In search of serological markers for HBV was observed that had the HBsAg 0.4%, 10% anti-HBc and 34% anti-HBs. Based on the interpretation of serological markers surveyed 62% of employees are susceptible to HBV infection. The age group 41-60 years, the service time, where 72% of servers that had come in contact with HBV had more than three years service in the hospital was more frequent among employees reagents. The vaccination for HBV has been observed that among the servers that had come in contact with the virus most of them 84% had completed the immunization schedule. The results of this study highlights the need for intensification of strategies to improve vaccination coverage against hepatitis B, training of professionals about preventive measures against accidents with biological material and professional awareness of the use of personal protection equipment and collective.
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)
Avaliação do estado secretor ABH e Lewis em mulheres não grávidas com e sem risco de desenvolver vulvovaginite por Candida sp
(Universidade Federal do Pará, 2003) CARNEIRO, Ligia Maia; CORVELO, Tereza Cristina de Oliveira; http://lattes.cnpq.br/7253864056606024
Na epidemiologic study of Candida sp infection prevalence in non-pregnant women was performed in a population of the north of Brazil (Belem-Pa, 2002). This paper aims to contribute to clear up the infection mechanisms of Candida sp and its possible association to ABO and Lewis group blood antigens and ABH substances secretory status. Such paper comprehended a total of 165 women admitted at the out-patient clinic of "Hospital da Policia Militar" and "Laboratorio de Analises Clinicas do Centro de Ciencias Biologicas da Universidade Federal do Para", who came to those units to undergo gynaecologic examinations, where blood, salive and vaginal mucus samples were taken. Candida sp infection presence was determined through the examination of fresh vaginal secretion and bacterioscopy of vaginal secretion. The identification of ABH and Lewis phenotipes in the blood was determined through direct hemaglutination tests and, in the salive, by Elisa Dot-blot. It was performed a standard form for the obtaining of epidemiologic information. Candida sp prevalation was 47.9%. Among the most commom signals and symptoms associed to Candida sp infections are pruritus and gleet. Women under 40 who did not use condoms and who have already had previous infections presented a higher risk of vulvo-vaginal infection caused by Candida sp. Infected and non-infected women with Candida sp had similar distribuition to the phenotypes of ABO, Lewis blood groups and ABH substances secretory status. And, comparing the expressions of Lewis antigens in the blood, save and vaginal mucus, it was verified that both secretions expressed Lewis antigens without any close relationship to erithrocitic Lewis phenotypes. In such context, it is considered that the nature of genetics diversity in the interaction between Candida sp and host requires more studies involving the identification of different types to determine their probable associations among ABH and Lewis blood groups phenotypes with cadidiasis.
Acesso aberto (Open Access)
Caracterização da resposta imune citocínica na infecção humana pelo vírus oropouche e sua relação com o padrão de soroconversão e a presença de sintomas
(Universidade Federal do Pará, 2011-12-19) OLIVEIRA, Euzébio de; VASCONCELOS, Pedro Fernando da Costa; http://lattes.cnpq.br/0973550817356564
This thesis is the first global study that researches and analyzes the immune response of cytokine in human infections by Orthobunyavirus Oropuche virus. The study used 320 samples of human serum. Sixty were from the Blood Bank (negative control) and 260 were obtained from two outbreaks of the Oropouche virus in the State of Pará and Amapá (Brazil). The latter was divided into 8 subgroups for better data accuracy. The collected samples were analyzed for clinical data/symptoms with serologic testing by titration of antibodies by the hemagglutination inhibition (IgM/IgG) and the detection cytokines plasma levels by flow cytometry. This allowed for the technical description of cytokine. The data obtained allowed for the observation of the characteristics and the behavior of the cytokines signatures expressed by patients by the presence or not of the virus. This also allowed for the observation of changes to serum through the presence of specific symptoms such as fever, chills, headache and dizziness. This led to the following conclusions a) there is a pattern in the synthesis of pro-inflammatory and regulatory cytokines; b) there is a balance in the profile of the immune response between pro-inflammatory cytokines (Th1) and modulators (Th17); c) an infection by the Oropouche virus alters the production of cytokines in individuals; d) the results also show that whem comparing individuals no responders with early responders, there was an increase of IL-1β and decreased IL- 12; no responders with late responders, there was a decrease of IL-8, and increased IFN-α, IL-23 and IL-17; No responders occurred early responders compared with the increase IL-4 and IFN-g; However, when compared early responders and late responders, decreased IFN-α and IL-6; early responders generally showed a decrease in IL-10 and late responders showed an increase in IL-5; e) The results also show the expression of IL-5 in patients who showed symptoms specific for Oropouche infection (fever, chills, headache and dizziness), suggesting this signal to be directly associated with pathogenesis of the virus; f) there is a need to complement this research with more studies such as those related to the expression of chemokines.
Acesso aberto (Open Access)
Caracterização da resposta inflamatória e alterações neuroquímicas e eletrofisiológicas do tecido retiniano em modelo murino de malária cerebral induzido pela infecção por Plasmodium Berghei ANKA
(Universidade Federal do Pará, 2015-02-19) LEÃO, Luana Ketlen Reis; SILVA, Anderson Manoel Herculano Oliveira da; http://lattes.cnpq.br/8407177208423247; OLIVEIRA, Karen Renata Herculano Matos; http://lattes.cnpq.br/3032008039259369
Cerebral malaria (CM) is one of the most serious complications resulting from infection by P. falciparum and the leading cause of death in children. The CM frame has a complex pathogenesis associated with neurological complications arising in an enhanced immune response as well as hemorrhagic events. Studies describing retinopathy associated with the frame, together with an intense process of astrogliosis in the vicinity of retinal vessels that nourish the tissue. This paper sought to characterize the inflammatory process and the possible neurochemical and electrophysiological changes in the retinal tissue of Swiss albino mice, when inoculated with Plasmodium berghei ANKA strain (PbA). Swiss albino mice were infected with PbA strain. To characterize the above experimental cerebral malaria (ECM) was evaluated several parameters, such as onset of clinical signs, survival curves parasitemia (%) and body mass gain, vascular permeability and quantification of cytokines (TNF-α, IL-6 and IL-10) in the cortical tissue. To evaluate changes in retinal tissue functionality, use full-field electroretinography. For the evaluation of neurotransmitter systems release assay was performed and uptake of glutamate and GABA which was then quantified by High Performance Liquid Chromatography. The inflammatory response analysis was performed to quantify the cytokines (TNF-α, IL-6 and IL-10) in retinal tissue. After characterizing the MCE framework we observe a reduction in the amplitude of b-wave of rods and cones, as well as increase the implicit time of rods, mixed responses at different intensities and oscillatory potential. We observed an increase in the release and glutamate uptake and also the activation of an anti-inflammatory pathway in retinal tissue. This study allowed us to validate the murine model of MCE and characterize for the first time, changes in the retinal function accompanied by changes in the glutamatergic system as well as activation of the inflammatory pathway in retinal tissue.
Acesso aberto (Open Access)
Caracterização sorológica e detecção molecular do HTLV em amostras de pacientes com distúrbios neurológicos no Estado do Pará, Brasil (1996-2005)
(Universidade Federal do Pará, 2006-07-07) LIMA, Telma Vitorina Ribeiro; LINHARES, Alexandre da Costa; http://lattes.cnpq.br/3316632173870389
Human T-lymphotropic virus tipe 1 is recognized as the etiologic agent of tropical spastic paraparesis/HTLV-1 associated myelopathy (TSP/HAM). A very similar clinical disease has been increasingly associated to HTLV-2, whose pathogenicity still requires further assessments. This transversal, retrospective epidemiological survey aimed to determine the prevalence of HTLV among individuals with neurological disturbances and further evaluate cases of inconclusive serology using molecular biology methods. The present study involved patients inhabitants of Pará State and/or admitted at health institutions of the and who were referred to the Virology Section of Instituto Evandro Chagas (IEC) by local doctors between January of 1996 and December 2005, to search for the presence of HTLV-1/2 serum antibodies. Of these patients 353 were selected, with age between 9 months and 79 years, who presented at least one signal or symptom of the Marsh’s Complex (1996), as well as had HTLV-1/2 positive serology at screening and confirmatory ELISA. The overall prevalence of HTLV antibodies by ELISA as 8,8% (31/353), with rates of 10,6% (19/179) and 6,9% (12/174) for female and male patients, respectively. Among HTLV-1/2 the 31 ELISA-positive patients it was noted that 15 (48.4%) of 31 had paresis (n = 8), parestesis (n = 5), and paraplegia (n = 3). Of these 31 HTLV ELISA positive patients, 25 could be submitted to WB for assessment of viral types, which were distributed as follow: 80% (20/25) were HTLV-1, 12% (3/25) were HTLV-2, one case was of HTLV-1+HTLV-2 infection (4%), and serum from one patient yielded an indeterminate profile (4%). Only 14 of these 25 patients could be re-localised for collection of an additional sample for molecular analysis. It was observed that 78.6% of samples typed by WB had the proviral TAX region successfully amplified by nested-PCR. In addition, types were confirmed as based on results obtained from the amplification of the POL region using real-time PCR; this denoted good specificity and sensitivity of the WB used in this study. The sample defined as HTLV-1+HTLV-2 infection by WB was amplified in its TAX region but real time PCR confirmed HTLV-1 infection only. The patient with WB indeterminate profile and one of samples typed as HTLV-2 by WB were amplified by nested-PCR but the real time PCR was negative for HTLV-1 and HTLV-2 in both samples. One patient presenting clinical manifestations of crural myalgia and parestesia with duration of about 7 years reacted HTLV-2-positive by both WB and real-time PCR, a denoting a clear HTLV-2- related chronic myelopathy. This study has identified a case of possible vertical transmission in two distinct situations: a patient whose mother presented antibodies for HTLV-1 by WB and two sisters who reacted HTLV-1-positive by WB and real-time PCR. Although of epidemiological relevance, results from this study warrant further and broader analyses concerning the molecular epidemiology of HTLV types and subtypes HTLV. In addition, a more complete clinical assessment of neurological symptoms should be further performed, in order to better characterise cases of HTLV-related chronic myelopathy in our region.
Acesso aberto (Open Access)
Correlação entre a avaliação clínica e o padrão de resposta imunológica periférica de pacientes acometidos por Paraparesia espástica tropical/mielopatia associada ao Vírus linfotrópico de celulas T humanas do tipo 1 (HTLV-1)
(Universidade Federal do Pará, 2012) DIAS, George Alberto da Silva; FUZII, Hellen Thais; http://lattes.cnpq.br/0026958665547973
Human T lymphotropic virus type 1 (HTLV-1) is an exogenous retrovirus that persistently infects 20–30 million people worldwide. This virus is etiologically related to the development of adult T-cell leukemia (ATL) and HTLV-1-associated myelopathy/tropical spastic paraparesis (HAM/TSP) a chronic disease of the central nervous system. The majority of HTLV-1-infected individuals remain lifelong asymptomatic carriers (ACs) of the virus. However, about 3-5% can develop ATL or HAM/TSP. The virus preferentially infects CD4+ T cells – main host cell of HTLV-1 – and rapidly induces cell activation and proliferation and expression of many host genes, including IFN-γ. The exact mechanism underlying these immunological and clinical events still remains unknown. In the current study, we evaluated the peripheral immune response and correlated with clinical symptoms like spasticity and weakness of the lower extremities, and gait abnormalities. 28 HTLV-1 infected patients were studied. Eight of them developed HAM/TSP and 20 were ACs. Total RNA was extracted from peripheric limphomononuclear cells using the TrizolR reagent (Invitrogen, Carlsbad, CA, USA). The quantitative real-time PCR was performed to quantify IFN-γ, IL-4, IL-5 and IL-10. Total RNA (1μg) of each sample was subjected to reverse transcription with Superscript III (Invitrogen). Real-time PCR was performed in StepOne Plus (Applied Biosystems, Foster City, CA) and signal detection was obtained with the Sybr Green reagent (Applied Biosystems). The amount of mRNA in the sample was expressed as the relative amount to the GAPDH and β-actin genes, according to the formula 2-ΔCT, where ΔCT is CTgene – CThousekeeping. The clinical symptoms of each patient were examined. Spasticity was assessed on the Modified Ashworth Scale, the weakness of the lower limb was measured using a manual scale, and the gait was given scores to the devices that assist in gait. The HAM/TSP patients showed higher expression of IFN-γ (Median: 2,9 x 10-3) than Acs (Median: 1,1 x 10-3), with p = 0,0710. The IFN-γ expression was positively correlated to spasticity (r = 0,2795), weakness (r = 0,6580) and gait (r = 0,7216). Interestingly, patients who need wheelchairs had a higher IFN-γ expression than those who don’t need wheelchair (p = 0,0371). The HAM/TSP patients showed higher Th1 response than ACs. The higher IFN-γ expression is correlated with the development and progression of the HAM/TSP.
Acesso aberto (Open Access)
Detecção in situ de citocinas de perfil TH1 e TH2 por imunoistoquímica e relação com a atividade de macrófagos nas formas polares da doença de Hansen
(Universidade Federal do Pará, 2009) SILVA, Dayse Danielle de Oliveira; QUARESMA, Juarez Antônio Simões; http://lattes.cnpq.br/3350166863853054
Leprosy is an infectious disease that has a slow and progressive evolution, with high incidence and prevalence in the states that compose the Legal Amazon. Considering the number of cases, the Pará state plays a prominent role in the national context. In order to evaluate the cytokine profile and the macrophages activity in the polar forms of leprosy and correlate with their histopathological aspects, a transversal study was performed, with a sample of 29 patients who had one of the polar forms of leprosy, namely tuberculoid or virchowian, from who skin biopsies of leprosy lesions were taken. It could be observed, through the analysis of this immunohistochemical material, that the studied groups showed no significant variation in the levels of IL-10, TGF-β, CD68, iNOS and Lysozyme. The levels of IL-4 were not expressive in the analyzed tissues and the levels of IFN-γ were higher in patients in the MHV group. In the virchowian pole, all cytokines tended towards a negative correlation with the macrophages activity. In the tuberculoid pole, the level of IL-10 showed a negative correlation with the levels of iNOS, IFN-γ and lysozyme, indicating a macrophage activity inhibition for this cytokine. It can be concluded that there is no difference in cytokine expression of TH1 and TH2 profile in polar forms of Hansen's disease and cytokines have a tendency to negative correlation with the activity of macrophages in MHV pole and a tendency to positive correlation in the pole MHT. Further research is needed to clarify why some populations have more susceptibility to leprosy than others. A similar study with a larger number of individuals may have a more significant outcome.
Acesso aberto (Open Access)
Estado nutricional e marcadores clínico-bioquímicos em indivíduos portadores de carcinoma gastrointestinal
(Universidade Federal do Pará, 2014-11-04) MIRANDA, Tayana Vago de; ARAÚJO, Marília de Souza; http://lattes.cnpq.br/9371703949781020
The nutritional status of patients with gastrointestinal carcinoma is frequently affected, being aggravated by the carcinogenesis that promote activation of the inflammatory process and subsequent activation of the immune system, with production of cytokines and acute phase proteins, such as C-reactive protein, which results in hypermetabolism, accelerating weight loss and progresses to cachexia. This study aimed to analyze the nutritional status and biochemical-clinical markers in patients with gastrointestinal carcinoma, treated at Hospital Universitário João de Barros Barreto (HUJBB), in Belém-PA. Was conducted a descriptive, observational and cross-sectional study involving patients with gastrointestinal carcinoma treated at HUJBB from december 2013 to july 2014. Nutritional assessment was conducted by anthropometric parameters, which included body mass index (BMI), percentage weight loss (%PWL), arm circumference (AC), arm muscle circumference (AMC), arm muscle area corrected (CAMA), triceps skinfold thickness (TST) and muscle adductor pollicis (MAP), biochemical parameters, by classifying hemoglobin, total lymphocyte count (TLC), albumin, transferrin, index-inflammatory nutritional prognosis (IPIN ) and subjective parameters, using the subjective global assessment produced by the patient (ASG-PPP), besides the identification and classification of cachexia. 44 patients were evaluated, 63.3% were male with a mean age of 61.2 years (±13.3); 95.50% were natural of Pará, 45.50% living in the countryside, 50.00% had incomplete education in primary and 52.30% had no family income. 63.60% of the patients evaluated, had stomach cancer; of these, 50.00% were in clinical stage IV and 73.30% in surgical treatment, with an average hospital stay of 45.85 days (± 32.97). In nutritional assessment was obtained 20.50% eutrophy in adults and 42.30% for seniors through BMI, however, in isolated assessment of muscle and fat compartments, there was 59.10% of severe depletion by of CAMA, 54.50% by the TST, 75.00% with the presence of depletion in AC and 68.18% in AMC. Severe weight loss was observed in 61.36% of the patients and in the MAP was obtained higher prevalence of moderate depletion (30.20%). At biochemical parameters, there was severe reduction in hemoglobin to 61.40% of patients, slight depletion of CTL in 56.80%, 47.70% for albumin and 45.50% with moderate depletion in transferrin. In the assessment of IPIN, was obtained medium risk complication for 56.80% of the patients. In ASG-PPP, 63.60% of patients were classified into severe malnutrition and the presence of symptomatic cachexia, was 54.50%. With regard to the correlation analysis, it was found that there was a positive and significant correlation of BMI with AMC, AC, TST, CAMA, MAP and hemoglobin; AMC with AC, and CAMA; AC with TST, CAMA, MAP, and hemoglobin; TST, CAMA; CAMA with MAP. In the principal component analysis, it was found as the most sensitive methods to detect malnutrition the assessment of AC, CAMA, AMC, BMI, TST, MAP, IPIN and evaluation of cachexia. Thus, the results obtained in this study indicate the nutritional impairment in patients with gastrointestinal carcinoma by different parameters, thus demonstrating that malnutrition occurs globally, with loss of both adipose tissue, muscle tissue as well as changes biochemical level.
Acesso aberto (Open Access)
Estudo da ação da crotoxina sobre o perfil de ativação de macrófagos peritoneais infectados com Leishmania (Leishmania) amazonensis
(Universidade Federal do Pará, 2016-04-12) FARIAS, Luis Henrique Seabra de; SILVA, Edilene Oliveira da; http://lattes.cnpq.br/7410116802190343
American Tegumentary Leishmaniasis (ATL) is a parasitic disease widely spread in most countries of Latin America, and caused by different species of the genus Leishmania. This protozoan is an obligate intracellular parasite that developed mechanisms to subvert the microbicidal activity of macrophages, such as inhibition of reactive oxygen species (ROS) and nitric oxide (NO) production. The chemotherapy is one of the most effective treatments for this disease, although the antileishmanial drugs available are in general toxic, expensive and require long-term treatment. Thus, the development of new natural products to treat leishmaniasis has become a priority. Ophidian toxins are natural sources of bioactive products with therapeutic properties already described. Therefore, we considered analyze the activity of crotoxin (CTX), a dimeric protein and the main neurotoxic component of Crotalus durissus terrificus snake venom, against promastigotes of Leishmania (L.) amazonensis and macrophages. The toxin significantly decreasing of 32,5% on the growth of promastigotes at 1,2μg/mL and 24,9% at 4,8μg/mL after 96 hours of treatment (IC50= 22,86μg/mL). The colorimetric assay (MTT) showed that this compound presented no cytotoxic effects against macrophages. Interestingly, CTX treated macrophages presented a significant higher capacity to metabolize the MTT substrate (mean= 59,78% ±3,31, higher) when compared with untreated control. It was observed that treated macrophages presented intense production of ROS (mean= 35,95% ±2,76, higher) when compared with untreated cells. Treated macrophages presented increased phagocytic activity and were capable to eliminate intracellular parasites. Besides that, these cells had it NO and pro-inflammatory cytokines production increased and morphological alteration that characterizes the M1 cellular activation profile. That activation culminates with the parasite elimination throughout host response, reverting the anergic action promoted by L. amazonensis, thereby leading to a good disease prognostic, evidencing that this compound could be a promising antileishmanial agent.
Acesso aberto (Open Access)
Estudo morfológico e imunológico da encefalite induzida pelo vírus juruaçá em modelo murino
(Universidade Federal do Pará, 2013-10-08) FERREIRA, Natalie Chaves; DINIZ JUNIOR, José Antônio Picanço; http://lattes.cnpq.br/1897655177251738
Many studies have been conducted to understand the neuropathogenesis of viral encephalitis from experimental work, however, no experimental studies have been devoted to understanding the neuropathogenesis of members of the Picornaviridae family isolated from bats in the Amazon region. The Juruaçá virus, one of these agents, partially characterized as a member of the Picornaviridae family by Araujo et al. (2006), caused lesions in the brain of neonatal mice with reactive gliosis presence, although not cause cytopathic effect (CPE) in primary cultures of central nervous system (CNS) cells, suggesting that this viral agent is responsible for the death of animals due to an intense immune response. The aim of this study was to investigate the immune response in the CNS and cellular changes caused by Juruaçá virus in newborn albino mice of strain BALB/c from histopathological analysis, microglial activation, and expression of cytokines, nitric oxide (NO) and reactive oxygen species (ROS). Thus, we performed sample processing for histopathology, immunosorbent assay, immunohistochemical and immunofluorescence assays, tests to quantify NO and superoxide radicals, and statistical analysis. Our results demonstrated that the Juruaçá virus induces lesions throughout the brain, with greater intensity in the cortical parenchyma. Immunohistochemical tests showed the presence of viral antigens and reactive microglias distributed throughout the brain and anterior spinal cord. Microglias with amoeboid shape, demonstrating intense activation, were observed in the cerebral cortex, olfactory bulb, anterior olfactory nucleus, midbrain and forebrain near the lateral ventricle. The production of anti-inflammatory cytokines (IL-10 and IL-4) decreased over time, whereas pro-inflammatory cytokines (IL -12, IL- 6, IL- 1β, TNF-α and IFN-γ) increased significantly from the 8th day. Assays for ROS detection showed great superoxide radicals production from the 4th day, as NO production was always lower in the infected animals. Probably, activation of glial cells, especially microglias, and subsequent production of proinflammatory cytokines and ROS promoted a devastating action on the cells of the CNS, which coincides with the intensification of clinical signs. In accordance with what has been explained above, became evident that our results indicate that the Juruaçá virus is responsible for a imprint inflammatory disease that leads to death 100% of infected neonates mice.
Acesso aberto (Open Access)
Helicobacter pylori em crianças e associação de cepas CagA na transmissão mãe-filho na Amazônia brasileira
(Universidade Federal do Pará, 2009-06) D’ANNIBALE, Vivian Lúcia Aslan; MARTINS, Luisa Caricio; CARNEIRO, Lígia Maia; BARILE, Katarine Antonia dos Santos; CORVELO, Tereza Cristina de Oliveira
The prevalence of Helicobacter pylori infection was investigated in blood samples from 100 children aged 1 to 12 years and from their mothers, by means of the indirect hemagglutination and anti-CagA methods, using ELISA assays. From these 100 children, 79 stool samples were obtained and bacterial antigens in the stools were investigated using capture ELISA. The antigens were detected in 54.4% (43/79) of the children, and serum antibodies in 43% (34/79). These methods presented similar performance, with greatest disagreement among the children aged 1 to 4 years. The seroprevalence was 50% (50/100) among the children and 86% (86/100) among the mothers. Infected mothers represented a risk factor that was 19 times greater than that of seronegative mothers, with regard to infecting their children (p < 0.05), especially the mothers with CagA+ strains (p < 0.05). Direct person-to-person contact may be a transmission method for this infection.
Acesso aberto (Open Access)
Implicações do perfil citocínico TH22 nas formas polares da hanseníase
(Universidade Federal do Pará, 2016-08-29) SILVEIRA, Edvaldo Lima; QUARESMA, Juarez Antônio Simões; http://lattes.cnpq.br/3350166863853054
BACKGROUND: Leprosy is a chronic granulomatous disease caused by Mycobacterium leprae. Among the immunopathological aspects of leprosy is known that the defense is done by the cellular immune response, able to phagocyte and destroy the bacilli, mediated by cytokines and mediators from oxidation. The long-standing concept of a Th1-Th2 dichotomy in leprosy, with predominant Th1 in tuberculoid lesions and Th2 predominant in virchowian pacients, has recently been challenged. Furthermore, the Th22 response was identified as modulating Th1-Th2 in inflammatory skin diseases, but their roles in leprosy have not yet been elucidated. OBJECTIVE: Evaluate the tissue expression of cytokines involved in Th22 response in the polar forms of leprosy. METHOD: Patients with dermato-immunological diagnosis of leprosy were included and selected 31 patients, 16 with the tuberculoid (TT) form and 15 with lepromatous (LL). Immunohistochemistry for tissue immunostaining with antibodies against IL-13, IL-22, TNF-α and FGF-b was based on the method involving the formation of biotin-streptavidin peroxidase complex. Quantitation of the immunostaining was taken randomly from 05 fields viewed at 400x magnification microscope. In univariate analysis, frequencies, measures of central tendency and dispersion were obtained and for investigation of the hypothesis were applied the Mann-Whitney test and the Pearson correlation, considering a significance level of 5% (p ≤ 0.05). RESULTS: Regarding the immunostaining for IL-22 can be observed statistical difference among the groups and in the LL pole the average was 241.3 ± 44.63 cells/mm2, while in the TT form the mean was 90.39 ± 30.18 cells/mm2 (p <0.0001). Engaging the presence of IL-13, LL pole average occurrence was 85.76 ± 19.99 cells/mm2. In the TT pole the mean was 57.20 ± 14.73 cells/mm2 (p = 0.0002). Regarding the immunostaining for FGF-b, in the LL lesions, the mean incidence was 228.9 ± 45.13 cells/mm2, while in the TT form the mean was 47.80 ± 14.29 cells/mm2 (p <0,0001). For TNF-α, quantitative analysis was statistically significant in TT form where the average of the cells expressing the cytokine was 99.74 ± 30.14 cells/mm2 when compared to the LL form where the results were 62.08 ± 13.67 cells/ mm2 (p = 0.0008). CONCLUSION: The Th-22 response, mediated by IL-22, has fundamental importance in the pathogenesis of leprosy, relating directly to the clinical form of the disease and other cytokines.
Acesso aberto (Open Access)
Imunomarcação tecidual para o fator XIIIa+ em dendrócitos dérmicos de lesões cutâneas com doença de Jorge Lobo
(Universidade Federal do Pará, 2010) CARNEIRO, Clivia Maria Moraes de Oliveira; BRITO, Arival Cardoso de; http://lattes.cnpq.br/0563291980190339
Jorge Lobo's disease (DJL) is a deep fungal infection caused by Lacazia loboi which mainly affects males farmers, with the clinical form keloid and location of the lower limbs. The highest incidence is found in the Brazilian Amazonia. There are few reports on immune tissue lesions of patients. This study aims to evaluate a possible role in the pathogenesis of the disease by factor XIIIa dermal dendrocytes (FXIIIa DD) in skin lesions, using the technique of immunohistochemistry. 33 skin biopsies were analyzed from patients with DJL. The control group consisted of 10 normal skin biopsies originating from patients without dermatological diseases and 61 biopsies from patients with paracoccidioidomycosis (PCM). The results obtained by records analyzing patients' revealed that DJL affects mainly men (84.8%), farmers (72.7%) with 46-65 years old (51.5%), coming from the northeastern Pará state (51.5%) with clinical form keloid (81.8%) and predominant location of lesions in the lower limbs (45.5). The values of the count of FXIIIa DD in skin lesions of DJL were not affected by variations in gender, age, occupation, origin, clinical manifestation and localization of lesions. The amount of FXIIIa DD in patients with DJL was higher than that found in the control group of patients with healthy skin and in the group of patients with PCM to both the histopathology of loose granuloma (GF) and organized granuloma (GBO). Because of FXIIIa DD be considered precursors of Langerhans cells (LCs) can be suggested that their increase in DJL reflects a reservoir for the LCs and transform them time and again, don’t allowing their decrease. It has been demonstrated the increase in the levels of Th2 cytokines (TGF-β) in the DJL, and the increase of FXIIIa DD that is able to secrete the factor TNF-α, observed in this study, shows a dominance of Th1. Whereas there is a co expression of cytokine profiles of both, the study suggests the existence of mixed patterns. So, the results obtained in this work suggest that DJL is a spectral disease, with a tendency of resistance or susceptibility. What might explain the existence of focal cases even with long duration of disease and disseminated cases like early manifestation of DJL.
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Imunopatologia experimental do vírus da raiva, com as variantes antigênicas 2 e 3
(Universidade Federal do Pará, 2015-06-02) CASSEB, Livia Medeiros Neves; VASCONCELOS, Pedro Fernando da Costa; http://lattes.cnpq.br/0973550817356564
The rabies is considered a zoonosis due have as host, reservoirs and transmitters the domestic or wild mammals. It´s characterized in acute disease caused by rabies virus (RABV) that affects the central nervous system (CNS) characterized by encephalitis with fatal prognosis in almost all cases, in any mammalian species. The aim of this study was to describe pathological findings and immunopathology of different strains of rabies virus in the tissues of the central nervous system, checking cellular and humoral immune response during experimental infection of Mus musculus mice. The animals were inoculated with two antigenic variants of RABV (VAg2 and VAg3), by different routes of infection, and a control group. The animals were observed for development of clinical signs and symptoms, collected and euthanized following a kinetic. The tissues were fixed in formaldehyde 10%, embedded in paraffin, stained with hematoxylin-eosin for histopathological analysis and with specific antibodies for immunohistochemical to characterize and quantify in situ distribution of the antigen and the inflammatory response. RABV antigens were found in the CNS in a diffuse way, but mainly in neurons. It was observed suppression of CD4+ lymphocytes, with increase of CD8+ lymphocytes. It was observed significant apoptosis with glial cell death and an increase of proinflammatory cytokines (TNF-α, IFN-γ, IL-6, IL-1β and IL-8), anti-inflammatory (TGF-β and IL-4) and iNOS in both antigenic variants of RABV, but without observation of a TH17 profile. The analyses enable the characterization of rabies as meningoencephalitis, since it affects the meningeal, perivascular and intraparenchymal microenvironments. And the inflammatory process was observed even in the presence of inclusion bodies, but with less intensity.
Acesso aberto (Open Access)
Imunoreatividade para tgf- β e caspase-3 e sua relação com o controle da resposta imune tecidual nas formas polares da hanseníase
(Universidade Federal do Pará, 2007-11-30) ALMEIDA, Fabricio Anderson Carvalho; QUARESMA, Juarez Antônio Simões; http://lattes.cnpq.br/3350166863853054
Leprosy is a chronic infect-contagious disease that accompanies the humanity for many years. Brazil occupies the second place in numbers of cases, and the state of Para is that presents the largest number of absolute cases. This study had as objective to evaluate the immunorreactivity for TGF-β and caspase-3 in the lepromatous and tuberculoid clinical forms of the leprosy evil trying to correlate the immunomarking pattern with the tissue control of the immune response of the host to the bacillus, through a retrospective study of paraffin enclosed tissue of 30 patients, being fifteen presenting in the lepromatous form and fifteen with the tuberculoid type of disease. The patients followed the protocol of leprosy diagnosis according to criteria of Health Ministry of Brazil and histopathologic features. It was observed that the lepromatous form of the leprosy presented a significant statistically correlation (p=0,4630) among TGF-β to caspase-3, evidencing that as the cytokine as the imunomarking of the apoptosis increase inch by inch and simultaneously in this polar form and that indirectly appear to a role of TGF-β in the control of the immunologic response in its place to the infection for the Mycobacterium leprae.
Acesso aberto (Open Access)
Infecção persistente pelos flavivírus Ilhéus e Rocio em hamsters dourados jovens (Mesocricetus auratus)
(Universidade Federal do Pará, 2009-08-28) HENRIQUES, Daniele Freitas; VASCONCELOS, Pedro Fernando da Costa; http://lattes.cnpq.br/0973550817356564
Ilheus (ILHV) and Rocio (ROCV) are flaviviruses (family Flaviviridae, genus Flavivirus) of great importance to public health in Brazil because these viruses are associated to encephalitis cases in humans. Recent studies have reported persistence of experimental infections (in vivo and in vitro) and clinical reports. The purpose of this study was to investigate in vivo the possible occurrence of persistent infection caused by ILHV and ROCV using young golden hamsters (Mesocricetus auratus) as experimental model. Hamsters were inoculated intraperitoneally with a suspension of brains of newborn mice infected with titers of 9.8 and 9.6 DL50/ 0.02 mL of ROCV and ILHV respectively, and at pre-determined intervals, they were anesthetized and sacrificed for collection of blood samples, serum and urine and organ fragments during four months (120 days) post-inoculation (p.i.). Viral quantification was calculated in samples of brain, liver and blood, using the technique of Real Time RT-PCR (qRT-PCR). All collected specimens were inoculated into VERO cells for confirmation of viral replication; and viral antigens in the cell cultures were detected by indirect immunofluorescence test; the levels of antibodies were determined by hemagglutination-inhibition test. Histopathological examination by hematoxylin-eosin and detection of viral antigens by imunohistochemistry were assayed in viscera and central nervous tissue samples collected during the kinetics. The study showed that young golden hamsters are good experimental model for persistent infection by the flaviviruses ILHV and ROCV. Both viruses induced strong immune response, although the levels of antibodies to ILHV were greater than for ROCV. The ROCV has demonstrated to be more pathogenic in these animals, suggesting higher ability to cause neuronal invasiveness than ILHV. Infected viscera samples inoculated in VERO cells resulted in growth of both viruses from all infected organ, blood, serum and urine samples and were confirmed by indirect immunofluorescence assay. Regarding persistence of infection, ROCV was detected in the brain, liver and blood by qRT-PCR, for three months p.i., while ILHV persistence was observed only in the brain for 30 days p.i. by qRT-PCR. The ROCV was able to produce histopathological changes, and immuno-labeled cells expressing viral antigens in liver, kidney, lung and brain samples during four month were confirmed by imunohistochemistry. To the ILHV, the histopathological changes and expression of viral antigens in samples from the liver, kidney and lung were only confirmed up to 30 days p.i., but the brain was positive for four months p.i.; The findings obtained in this study showed that both viruses have capacity to cause persistent infection in hamsters intraperitoneally infected, studies additional are needed to determine the pathophysiology and pathogenesis of ILHV and ROCV persistent infections.
Acesso aberto (Open Access)
Influências da idade e do ambiente sobre o curso temporal da infecção pelo vírus da Dengue acentuada por anticorpo heterólogo em modelo murino: ensaios comportamentais e histopatológicos
(Universidade Federal do Pará, 2014-01-03) DINIZ, Daniel Guerreiro; DINIZ, Cristovam Wanderley Picanço; http://lattes.cnpq.br/2014918752636286
Because the enriched environment (EE) increases the activity of T cells, contribute to the immunopathogenesis of dengue virus infections (VDEN) we hypothesized that animals maintained in an enriched environment (AE) compared with animals from impoverished environment of standard laboratory cages (IE), would develop more severe forms of the disease. Because older animals have less functional decline in adaptive immunity T cells, we tested the hypothesis that AE old mice would show higher number of deaths and more intense clinical signs than age-matched IE animals, and this would be associated with greater expansion of T lymphocytes. To test these hypotheses we established scheme of multiple inoculations in adult animals of 9 and 18 months of age. Two regimens of inoculation were tested: multiple injections of single serotype (VDEN3 genotype III) infected brain homogenate (SS) or alternatively multiple injections with that infected brain homogenate followed 24h later by inoculation of heterologous antibody (SSHA). In both cases multiple i.p. inoculations were done. It was found significant differences in the temporal progression of the disease in the animals submitted to one or another scheme of inoculation: SSHA group (Kaplan -Meier log-rank test, p = 0.0025); IUS (Kaplan -Meier log-rank test, p = 0.089). The survival curves of AE and AP under SSHA regime were extended after a single injection of glucocorticoids, reducing the symptoms and the number of deaths, and these effects were greater in the EE group than in the IE (Kaplan-Meier log-rank test, p = 0.0162). In SSHA scheme, EE group showed clinical signs more intense than the AP and those included dyspnea, tremor, hunched posture, immobility, pre-terminal paralysis, shock and eventual death. Compared to the IE group, the AE group regardless of age showed higher mortality and more severe clinical signs. These more severe clinical signs in EE animals under SSHA regime were associated with increased hyperplasia of T lymphocytes in the spleen and increased infiltration of these cells in the liver, lungs and kidneys. Although lymphocytic hyperplasia and infiltration have been more intense in older than in younger animals, immunostaining for viral antigens in target organs was higher in young than in the aged mice. The presence of the virus in various infected organs were confirmed by real time PCR. Taken together the results suggest that the enriched environment life style exacerbates the subsequent inflammatory response to infection, and that is associated with more severe clinical symptoms, higher mortality and increased T cell expansion. Behavioral and histopathological data validate a new immunocompetent murine model for studies on dengue disease allowing in vivo tests of a number of hypothesis raised by epidemiological and in vitro studies.