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2.
Front Vet Sci ; 10: 1187271, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-37396996

RESUMO

Introduction: In veterinary medicine, cancer is the leading cause of death in companion animals, and mammary gland tumors represent the most common neoplasm in female dogs. Several epidemiological risk factors, such as age, breed, hormones, diet, and obesity have been reported to be relevant for canine mammary tumors. Nowadays, the gold standard for diagnosis of canine mammary tumors is the pathological examination of the suspected tissue. However, tumor grade can only be assessed after surgical removal or biopsy of the altered tissue. Therefore, in cases of tumors that could be surgically removed, it would be very helpful to be able to predict the biological behavior of the tumor, before performing any surgery. Since, inflammation constitutes part of the tumor microenvironment and it influences each step of tumorigenesis, cellular and biochemical blood markers of systemic inflammation, such as the neutrophil to lymphocyte ratio (NLR) and the albumin to globulin ratio (AGR) have been proposed as prognostic factors for human cancer development. The NLR and the AGR have not been explored enough as prognostic factors for cancer development in veterinary medicine. Methods: To determine the prognostic value of NLR in canine mammary tumors, clinical records including biochemistry and hematological studies of female dogs with mammary tumors and of control healthy dogs, were used to determine the pre-treatment NLR and AGR. Other clinical data included age, breed, tumor size, histological tumor grade, and survival time after surgery. Results and discussion: It was found that a higher pre-treatment NLR value (NLR > 5) associates with less survival rate. In contrast, the AGR did not show any predictive value on the malignancy of the tumor. However, by combining the NLR with AGR, age of the dog, and tumor size in a principal component analysis (PCA), the grade of the tumor and survival after surgery could be appropriately predicted. These data strongly suggest that pre-treatment NLR values have a prognostic value for the survival rate after surgery of dogs with mammary tumors.

3.
Toxicol In Vitro ; 62: 104681, 2020 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-31655123

RESUMO

Cytochrome P4501A1 (CYP1A1) is involved in the metabolism of several genotoxic/carcinogenic environmental xenobiotics including polycyclic aromatic hydrocarbons (PAHs) like benzo[a]pyrene. Several authors had proposed CYP1A inhibition as a plausible strategy for cancer chemoprevention. Using ethoxyresorufin O-deethylase activity (EROD), we tested the inhibitory properties of nine flavonoids: quercetin, miricetin, luteolin, fisetin, morin, kaempferol, 5-hydroxyflavone (5-HF), 3-hydroxyflavone (3-HF), and flavone (F) against human recombinant CYP1A1. The last three compounds exerted the highest inhibitory effect with IC50 values of 0.07, 0.10 and 0.08 µM respectively; the more hydroxyl-groups were present, the lower the potency of inhibition was. Biochemical characterization leads to the conclusion that flavone and its hydroxy derivatives are mixed-type inhibitors. In silico studies have shown that, Phe224 and other aromatic residues in the human CYP1A1 active site play an important role in flavonoid-CYP interaction, through a π/π stacking between the aminoacid and the flavonoid C-ring. Outside the active site, the three flavonoids bind preferentially between A and K helices of the enzyme. Results from the Ames test using human S9 fraction revealed that none of the three compounds was mutagenic. We can consider 5-HF, 3-HF, and F as potential chemopreventive agents against genotoxic damage caused by metabolites resulting from CYP1A1 activity.


Assuntos
Antineoplásicos Fitogênicos/farmacologia , Citocromo P-450 CYP1A1/antagonistas & inibidores , Flavonoides/farmacologia , Aminoácidos/metabolismo , Antimutagênicos/farmacologia , Simulação por Computador , Flavonas/química , Flavonas/farmacologia , Humanos , Modelos Moleculares , Simulação de Acoplamento Molecular , Testes de Mutagenicidade , Mutagênicos/farmacologia , Proteínas Recombinantes , Relação Estrutura-Atividade
4.
Environ Mol Mutagen ; 60(5): 428-442, 2019 06.
Artigo em Inglês | MEDLINE | ID: mdl-30706525

RESUMO

Mexico City's Metropolitan Area (MCMA) includes Mexico City and 60 municipalities of the neighbor states. Inhabitants are exposed to emissions from over five million vehicles and stationary sources of air pollutants such as particulate matter (PM) and ozone. MCMA PM contains elemental carbon and organic carbon (OC). OCs include polycyclic aromatic hydrocarbons (PAHs), many of which induce mutagenic and carcinogenic DNA adducts. Gestational exposure to air pollution has been associated with increased risk of intrauterine growth restriction, preterm birth or low birth weight risk, and PAH-DNA adducts. These effects also depend on the presence of risk alleles. We investigated the presence of bulky PAH-DNA adducts, plasma 8-iso-PGF2α (8-iso-prostaglandin F2α ) and risk allele variants in neonates cord blood and their non-smoking mothers' leucocytes from families that were living in a highly polluted area during 2014-2015. The presence of adducts was significantly associated with both PM2.5 and PM10 levels, mainly during the last trimester of gestation in both neonates and mothers, while the last month of pregnancy was significant for the association between ozone levels and maternal plasma 8-iso-PGF2α . Fetal CYP1B1*3 risk allele was associated with increased adduct levels in neonates while the presence of the maternal allele significantly reduced the levels of fetal adducts. Maternal NQO1*2 was associated with lower maternal levels of adducts. Our findings suggest the need to reduce actual PM limits in MCMA. We did not observe a clear association between PM and/or adduct levels and neonate weight, length, body mass index, Apgar or Capurro score. Environ. Mol. Mutagen. 60:428-442, 2019. © 2019 Wiley Periodicals, Inc.


Assuntos
Adutos de DNA/análise , Exposição Materna , Troca Materno-Fetal/fisiologia , Ozônio/toxicidade , Material Particulado/toxicidade , Hidrocarbonetos Policíclicos Aromáticos/análise , Efeitos Tardios da Exposição Pré-Natal/patologia , Adulto , Poluição do Ar/análise , Citocromo P-450 CYP1B1/genética , Adutos de DNA/genética , Feminino , Sangue Fetal/química , Humanos , Recém-Nascido , Isoprostanos/sangue , México , NAD(P)H Desidrogenase (Quinona)/genética , Gravidez , Emissões de Veículos/análise , Adulto Jovem
5.
Parasitol Res ; 117(9): 2767-2784, 2018 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-29938323

RESUMO

Although helminth-Plasmodium coinfections are common in tropical regions, the implications of this co-existence for the host immune response are poorly understood. In order to understand the effect of helminth infection at different times of coinfection on the immune response against Plasmodium infection, BALB/c mice were intraperitoneally infected with Taenia crassiceps (Tc). At 2 (Tc2) or 8 (Tc8) weeks post-infection, mice were intravenously infected with 1 × 103 Plasmodium yoelii (Py) 17XL-parasitized red blood cells. Py 17XL-single-infected mice developed cachexia, splenomegaly, and anemia, and died at 11 days post-infection. Importantly, Tc2 + Py-coinfected mice showed increased survival of 58% on day 11, but developed pathology (cachexia and splenomegaly) and succumbed on day 18 post-coinfection, this latter associated with high levels of IL-1ß and IL-12, and reduced IFN-γ in serum compared with Py 17XL-single-infected mice. Interestingly, Tc8 + Py-coinfected mice showed increased survival up to 80% on day 11 and succumbed on day 30 post-coinfection. This increased survival rate conferred by chronic helminth infection was associated with a decreased pathology and mixed inflammatory-type 1/anti-inflammatory-type 2 immune profile as evidenced by the production of high levels of IL-12 and IL-10, and reduced TNF-α from macrophages, high levels of IL-4 and IL-10, and low levels of IFN-γ from spleen cells. Also high serum levels of IL-1ß, TNF-α, IL-12, IL-4, and IL-10, but a significant reduction of IFN-γ were observed. Together, these data indicate that polarization of the cell-mediated response modulated by a pre-existing helminth infection differentially impacts on the host immune response to Py 17XL in a time-dependent manner.


Assuntos
Coinfecção/parasitologia , Malária/imunologia , Plasmodium yoelii/imunologia , Taenia/imunologia , Teníase/imunologia , Anemia , Animais , Células Cultivadas , Eritrócitos/parasitologia , Feminino , Interleucina-10/sangue , Subunidade p35 da Interleucina-12/sangue , Macrófagos/imunologia , Malária/sangue , Malária/patologia , Camundongos , Camundongos Endogâmicos BALB C , Baço/imunologia , Esplenomegalia/parasitologia , Teníase/sangue , Teníase/patologia , Fator de Necrose Tumoral alfa/sangue
6.
Front Genet ; 9: 55, 2018.
Artigo em Inglês | MEDLINE | ID: mdl-29545822

RESUMO

Human macrophage migration inhibitory factor (MIF) is a cytokine that plays a role in several metabolic and inflammatory processes. Single nucleotide polymorphism (SNP) -173 G/C (rs755622) on MIF gene has been associated with numerous diseases, such as arthritis and cancer. However, most of the reports concerning the association of MIF with these and other pathologies are inconsistent and remain quite controversial. Therefore, we performed a meta-analysis from 96 case-control studies on -173 G/C MIF SNP and stratified the data according to the subjects geographic localization or the disease pathophysiology, in order to determine a more meaningful significance to this SNP. The polymorphism was strongly associated with an increased risk in autoimmune-inflammatory, infectious and age-related diseases on the dominant (OR: 0.74 [0.58-0.93], P < 0.01; OR: 0.81 [0.74-0.89], P < 0.0001; and OR: 0.81 [0.76-0.87], P < 0.0001, respectively) and the recessive models (OR: 0.74 [0.57-0.095], P < 0.01; OR: 0.66 [0.48-0.92], P < 0.0154; and OR: 0.70 [0.60-0.82], P < 0.0001, respectively). Also, significant association was found in the geographic localization setting for Asia, Europe and Latin America subdivisions in the dominant (OR: 0.76 [0.69-0.84], P < 0.0001; OR: 0.77 [0.72-0.83], P < 0.0001; OR: 0.61 [0.44-0.83], P-value: 0.0017, respectively) and overdominant models (OR: 0.85 [0.77-0.94], P < 0.0001; OR: 0.80 [0.75-0.86], P < 0.0001; OR: 0.73 [0.63-0.85], P-value: 0.0017, respectively). Afterwards, we implemented a network meta-analysis to compare the association of the polymorphism for two different subdivisions. We found a stronger association for autoimmune than for age-related or autoimmune-inflammatory diseases, and stronger association for infectious than for autoimmune-inflammatory diseases. We report for the first time a meta-analysis of rs755622 polymorphism with a variety of stratified diseases and populations. The study reveals a strong association of the polymorphism with autoimmune and infectious diseases. These results may help direct future research on MIF-173 G/C in diseases in which the relation is clearer and thus assist the search for more plausible applications.

7.
PLoS Negl Trop Dis ; 11(6): e0005646, 2017 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-28599004

RESUMO

BACKGROUND: Extraparenchymal neurocysticercosis (ExPNCC), an infection caused by Taenia solium cysticerci that mainly occurs in the ventricular compartment (Ve) or the basal subarachnoid space (SAb), is more severe but less frequent and much less studied than parenchymal neurocysticercosis (ParNCC). Demographic, clinical, radiological, and lumbar cerebrospinal fluid features of patients affected by ExPNCC are herein described and compared with those of ParNCC patients. METHODOLOGY AND PRINCIPAL FINDINGS: 429 patients with a confirmed diagnosis of neurocysticercosis, attending the Instituto Nacional de Neurología y Neurocirugía, a tertiary reference center in Mexico City, from 2000 through 2014, were included. Demographic information, signs and symptoms, radiological patterns, and lumbar cerebrospinal fluid (CSF) laboratory values were retrieved from medical records for all patients. Data were statistically analyzed to assess potential differences depending on cyst location and to determine the effects of age and sex on the disease presentation. In total, 238 ExPNCC and 191 ParNCC patients were included. With respect to parenchymal cysts, extraparenchymal parasites were diagnosed at an older age (P = 0.002), chiefly caused intracranial hypertension (P < 0.0001), were more frequently multiple and vesicular (P < 0.0001), and CSF from these patients showed higher protein concentration and cell count (P < 0.0001). SAb patients were diagnosed at an older age than Ve patients, and showed more frequently seizures, vesicular cysticerci, and higher CSF cellularity. Gender and age modulated some traits of the disease. CONCLUSIONS: This study evidenced clear clinical, radiological, and inflammatory differences between ExPNCC and ParNCC, and between SAb and Ve patients, and demonstrated that parasite location determines different pathological entities.


Assuntos
Inflamação/patologia , Neurocisticercose/patologia , Adulto , Encéfalo/parasitologia , Encéfalo/patologia , Humanos , Inflamação/parasitologia , México/epidemiologia , Pessoa de Meia-Idade , Neurocisticercose/epidemiologia , Estudos Retrospectivos
8.
Immunobiology ; 220(9): 1050-8, 2015 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-26026196

RESUMO

The early detection of cancer is one of the most promising approaches to reduce its growing burden and develop a curative treatment before the tumor is established. The early diagnosis of breast cancer is the most demanding of all tumors, because it is the most common cancer in women worldwide. We have described a new approach to analyze humoral immune reactions against 4 T1 cell antigens in female mice, reporting that the IgG and IgM responses differed and varied over time and between individuals. In this study, we compared and analyzed the detection of tumor antigens with IgG and IgM from the sera of male mice that were injected with 4 T1 cells into the mammary gland nipple in 2D immunoblot images. The variability in IgM and IgG responses in female and male mice with breast cancer at various stages of disease was characterized, and the properties with regard to antigen recognition were correlated statistically with variables that were associated with the individuals and tumors. The ensuing IgG and IgM responses differed. Only the IgG response decreased over time in female mice--not in male mice. The IgM response was maintained during tumor development in both sexes. Each mouse had a specific pattern of antigen recognition--ie, an immunological signature--represented by a unique set of antigen spots that were recognized by IgM or IgG. These data would support that rationale IgM is a better tool for early diagnosis, because it is not subject to immunosuppression like IgG in female mice with breast cancer.


Assuntos
Antígenos de Neoplasias/imunologia , Neoplasias da Mama/diagnóstico , Detecção Precoce de Câncer/métodos , Imunoglobulina G/sangue , Imunoglobulina M/sangue , Animais , Antígenos de Neoplasias/sangue , Neoplasias da Mama/imunologia , Linhagem Celular Tumoral , Modelos Animais de Doenças , Ensaio de Imunoadsorção Enzimática , Feminino , Imunidade Humoral/imunologia , Immunoblotting , Imunoglobulina G/imunologia , Imunoglobulina M/imunologia , Masculino , Camundongos , Camundongos Endogâmicos BALB C , Transplante de Neoplasias , Fatores Sexuais
9.
Hum Vaccin Immunother ; 10(11): 3201-13, 2014.
Artigo em Inglês | MEDLINE | ID: mdl-25483665

RESUMO

The antigenic variability of tumor cells leading to dynamic changes in cancer epitope landscape along with escape from immune surveillance by down-regulating tumor antigen expression/presentation and immune tolerance are major obstacles for the design of effective vaccines. We have developed a novel concept for immunogen construction based on introduction of massive mutations within the epitopes targeting antigenically variable pathogens and diseases. Previously, we showed that these immunogens carrying large combinatorial libraries of mutated epitope variants, termed as variable epitope libraries (VELs), induce potent, broad and long lasting CD8+IFN-γ+ T-cell response as well as HIV-neutralizing antibodies. In this proof-of-concept study, we tested immunogenic properties and anti-tumor effects of the VELs bearing survivin-derived CTL epitope (GWEPDDNPI) variants in an aggressive metastatic mouse 4T1 breast tumor model. The constructed VELs had complexities of 10,500 and 8,000 individual members, generated as combinatorial M13 phage display and synthetic peptide libraries, respectively, with structural composition GWXPXDXPI, where X is any of 20 natural amino acids. Statistically significant tumor growth inhibition was observed in BALB/c mice immunized with the VELs in both prophylactic and therapeutic settings. Vaccinated mice developed epitope-specific spleen cell and CD8+ IFN-γ+ T-cell responses that recognize more than 50% of the panel of 87 mutated epitope variants, as demonstrated in T-cell proliferation assays and FACS analysis. These data indicate the feasibility of the application of this new class of immunogens based on VEL concept as an alternative approach for the development of molecular vaccines against cancer.


Assuntos
Vacinas Anticâncer/imunologia , Epitopos de Linfócito T/imunologia , Proteínas Inibidoras de Apoptose/genética , Neoplasias Mamárias Experimentais/imunologia , Proteínas Repressoras/genética , Linfócitos T Citotóxicos/imunologia , Sequência de Aminoácidos , Animais , Antígenos de Neoplasias/imunologia , Linfócitos T CD4-Positivos/imunologia , Proliferação de Células , Células Cultivadas , Epitopos de Linfócito T/genética , Feminino , Tolerância Imunológica/imunologia , Interferon gama/imunologia , Ativação Linfocitária/imunologia , Neoplasias Mamárias Experimentais/genética , Neoplasias Mamárias Experimentais/prevenção & controle , Camundongos , Camundongos Endogâmicos BALB C , Biblioteca de Peptídeos , Survivina , Evasão Tumoral/imunologia , Vacinação , Vacinas Sintéticas/imunologia
10.
Mem Inst Oswaldo Cruz ; 108(7): 914-20, 2013 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-24271046

RESUMO

Neurocysticercosis (NC) is a clinically and radiologically heterogeneous parasitic disease caused by the establishment of larval Taenia solium in the human central nervous system. Host and/or parasite variations may be related to this observed heterogeneity. Genetic differences between pig and human-derived T. solium cysticerci have been reported previously. In this study, 28 cysticerci were surgically removed from 12 human NC patients, the mitochondrial gene that encodes cytochrome b was amplified from the cysticerci and genetic variations that may be related to NC heterogeneity were characterised. Nine different haplotypes (Ht), which were clustered in four haplogroups (Hg), were identified. Hg 3 and 4 exhibited a tendency to associate with age and gender, respectively. However, no significant associations were found between NC heterogeneity and the different T. solium cysticerci Ht or Hg. Parasite variants obtained from patients with similar NC clinical or radiological features were genetically closer than those found in groups of patients with a different NC profile when using the Mantel test. Overall, this study establishes the presence of genetic differences in the Cytb gene of T. solium isolated from human cysticerci and suggests that parasite variation could contribute to NC heterogeneity.


Assuntos
Citocromos b/genética , Variação Genética/genética , Neurocisticercose/parasitologia , Taenia solium/genética , Animais , Sequência de Bases , Humanos , Dados de Sequência Molecular , Taenia solium/isolamento & purificação
11.
Mem. Inst. Oswaldo Cruz ; 108(7): 914-920, 1jan. 2013. tab
Artigo em Inglês | LILACS | ID: lil-696019

RESUMO

Neurocysticercosis (NC) is a clinically and radiologically heterogeneous parasitic disease caused by the establishment of larval Taenia solium in the human central nervous system. Host and/or parasite variations may be related to this observed heterogeneity. Genetic differences between pig and human-derived T. solium cysticerci have been reported previously. In this study, 28 cysticerci were surgically removed from 12 human NC patients, the mitochondrial gene that encodes cytochrome b was amplified from the cysticerci and genetic variations that may be related to NC heterogeneity were characterised. Nine different haplotypes (Ht), which were clustered in four haplogroups (Hg), were identified. Hg 3 and 4 exhibited a tendency to associate with age and gender, respectively. However, no significant associations were found between NC heterogeneity and the different T. solium cysticerci Ht or Hg. Parasite variants obtained from patients with similar NC clinical or radiological features were genetically closer than those found in groups of patients with a different NC profile when using the Mantel test. Overall, this study establishes the presence of genetic differences in the Cytb gene of T. solium isolated from human cysticerci and suggests that parasite variation could contribute to NC heterogeneity. .


Assuntos
Animais , Humanos , Citocromos b/genética , Variação Genética/genética , Neurocisticercose/parasitologia , Taenia solium/genética , Sequência de Bases , Dados de Sequência Molecular , Taenia solium/isolamento & purificação
12.
PLoS Negl Trop Dis ; 7(3): e2096, 2013.
Artigo em Inglês | MEDLINE | ID: mdl-23505587

RESUMO

BACKGROUND: The most severe clinical form of neurocysticercosis (NC) occurs when cysticerci are located in the subarachnoid space at the base of the brain (SaB). The diagnosis, monitoring and treatment of NC-SaB, constitutes a severe clinical challenge. Herein we evaluate the potential of the HP10 antigen detection enzyme-linked immunosorbent assay (HP10 Ag-ELISA) in the long term follow-up of NC-SaB cases. Assay performance was compared with that of Magnetic Resonance Imaging (MRI). In addition, the robustness of the HP10 Ag-ELISA was evaluated independently at two different institutions. METHODOLOGY/PRINCIPAL FINDINGS: A double-blind prospective cohort trial was conducted involving 38 NC-SaB cases and a total of 108 paired serum and cerebrospinal fluid (CSF) samples taken at intervals of 4 to 8 months for up to 43 months. At each medical visit, results of sera and CSF HP10 Ag-ELISA and MRI obtained at last visit were compared and their accuracy was evaluated retrospectively, considering radiological evolution between appointments. In the long-term follow-up study, HP10 Ag-ELISA had a better agreement than MRI with retrospective radiological evaluation. High reproducibility of HP10 Ag-ELISA between laboratories was also demonstrated. CONCLUSIONS: Results reported in this study establish for the first time the usefulness of the comparatively low cost HP10 Ag-ELISA for long term follow-up of NC-SaB patients.


Assuntos
Antígenos de Helmintos/análise , Biomarcadores/análise , Técnicas de Laboratório Clínico/métodos , Monitoramento de Medicamentos/métodos , Neurocisticercose/diagnóstico , Neurocisticercose/tratamento farmacológico , Parasitologia/métodos , Adulto , Idoso , Antígenos de Helmintos/sangue , Antígenos de Helmintos/líquido cefalorraquidiano , Biomarcadores/sangue , Biomarcadores/líquido cefalorraquidiano , Encéfalo/diagnóstico por imagem , Técnicas de Laboratório Clínico/economia , Estudos de Coortes , Monitoramento de Medicamentos/economia , Ensaio de Imunoadsorção Enzimática/economia , Ensaio de Imunoadsorção Enzimática/métodos , Feminino , Humanos , Estudos Longitudinais , Imageamento por Ressonância Magnética , Masculino , Pessoa de Meia-Idade , Parasitologia/economia , Estudos Prospectivos , Radiografia , Ensaios Clínicos Controlados Aleatórios como Assunto
13.
Physiol Behav ; 106(2): 278-84, 2012 May 15.
Artigo em Inglês | MEDLINE | ID: mdl-22369853

RESUMO

N-(3-hydroxy-1, 3, 5 (10) estratrien-17beta-yl)-3-hydroxypropylamine (17ß aminoestrogen, prolame) is a steroidal compound with weak estrogen-related trophic-proliferative effects in uterus. Contrasting with 17ß-estradiol (E2) pro-coagulant effects, this compound has high anticoagulant and antiplatelet effects. It has been extensively demonstrated that E2 plays important roles in brain function. However, prolame's influence on central nervous system has not been documented. In this study, we evaluated the effects of prolame replacement in young ovariectomized rats on spatial learning and memory and anxiety, correlating pyramidal cell dendritic spine density changes and neuronal nitric oxide synthase (nNOS) expression in the hippocampus. Ovariectomized young rats were treated with prolame for 4 weeks. Three other groups were used as physiological, pathological, and pharmacological references as follow: gonadally intact cycling females, ovariectomized, and ovariectomized with 17ß-estradiol treatment respectively, for the same time period. Experiment 1 investigated the behavioral effects of prolame on anxiety and spatial learning using elevated plus maze (EPM) and Morris water maze (MWM) paradigms respectively. Experiment 2 studied the dendritic spine density and neuronal nitric oxide synthase expression in the hippocampus of the 4 experimental groups. Similar to estradiol, prolame reversed the anxiogenic effects of ovariectomy, evaluated by EPM, and enhanced MWM performance to the level of gonadally intact subjects. Hippocampi from prolame-treated rats exhibited enhanced nNOS immunoreactivity and its relocation in dendritic compartments, as well as recovery of dendritic spine density loss in pyramidal neurons. Hence, prolame may provide an alternative option for ameliorating neurological symptoms caused by surgical menopause.


Assuntos
Ansiedade/tratamento farmacológico , Estrenos/uso terapêutico , Terapia de Reposição Hormonal/psicologia , Deficiências da Aprendizagem/tratamento farmacológico , Transtornos da Memória/tratamento farmacológico , Óxido Nítrico Sintase Tipo I/biossíntese , Ovariectomia/efeitos adversos , Animais , Espinhas Dendríticas/ultraestrutura , Modelos Animais de Doenças , Avaliação Pré-Clínica de Medicamentos/métodos , Avaliação Pré-Clínica de Medicamentos/psicologia , Estradiol/farmacologia , Estradiol/uso terapêutico , Estrenos/síntese química , Estrenos/farmacologia , Feminino , Hipocampo/citologia , Hipocampo/metabolismo , Terapia de Reposição Hormonal/métodos , Aprendizagem em Labirinto/efeitos dos fármacos , Ratos , Ratos Wistar
14.
J Biomol Screen ; 15(10): 1268-73, 2010 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-20974903

RESUMO

In this study, the authors have generated a tapeworm Taenia solium genomic DNA expression library where foreign peptides/proteins were fused to N-termini of M13 cpVIII and expressed at a high copy number on the phage surface, and they showed that this library may be used in bioselection against antipathogen immune sera, allowing the identification of disease-related antigens recognizing antibodies present in clinical samples. They isolated 2 phage clones expressing T. solium-derived antigens specifically reacting with antibodies present in plasma and cerebrospinal fluid samples of neuroimaging-confirmed neurocysticercosis patients. The described antigen discovery strategy may be used for the direct identification of antigens useful for host-pathogen interaction studies as well as for the development of molecular vaccines and diagnostics.


Assuntos
Anticorpos Anti-Helmínticos/sangue , Anticorpos Anti-Helmínticos/líquido cefalorraquidiano , Anticorpos Anti-Helmínticos/imunologia , Neurocisticercose/imunologia , Taenia solium/imunologia , Animais , Anticorpos Anti-Helmínticos/genética , Antígenos de Helmintos/genética , Antígenos de Helmintos/imunologia , Bacteriófago M13/genética , Ensaio de Imunoadsorção Enzimática , Feminino , Biblioteca Genômica , Interações Hospedeiro-Parasita , Humanos , Imunoglobulina G/líquido cefalorraquidiano , Imunoglobulina G/imunologia , Camundongos , Camundongos Endogâmicos BALB C , Neurocisticercose/diagnóstico , Biblioteca de Peptídeos , Taenia solium/genética
15.
J Neuroimmunol ; 229(1-2): 248-55, 2010 Dec 15.
Artigo em Inglês | MEDLINE | ID: mdl-20864186

RESUMO

N-truncated/modified forms of amyloid beta (Aß) peptide are found in diffused and dense core plaques in Alzheimer's disease (AD) and Down's syndrome patients as well as animal models of AD, and represent highly desirable therapeutic targets. In the present study we have focused on N-truncated/modified Aß peptide bearing amino-terminal pyroglutamate at position 11 (AßN11(pE)). We identified two B-cell epitopes recognized by rabbit anti-AßN11(pE) polyclonal antibodies. Interestingly, rabbit anti-AßN11(pE) polyclonal antibodies bound also to full-length Aß1-42 and N-truncated/modified AßN3(pE), suggesting that the three peptides may share a common B-cell epitope. Importantly, rabbit anti-AßN11(pE) antibodies bound to naturally occurring Aß aggregates present in brain samples from AD patients. These results are potentially important for developing novel immunogens for targeting N-truncated/modified Aß aggregates as well, since the most commonly used immunogens in the majority of vaccine studies have been shown to induce antibodies that recognize the N-terminal immunodominant epitope (EFRH) of the full length Aß, which is absent in N-amino truncated peptides.


Assuntos
Peptídeos beta-Amiloides/metabolismo , Anticorpos/farmacologia , Linfócitos B/imunologia , Epitopos de Linfócito B/efeitos dos fármacos , Ácido Pirrolidonocarboxílico/imunologia , Doença de Alzheimer/patologia , Análise de Variância , Animais , Anticorpos Anti-Idiotípicos/imunologia , Anticorpos Anti-Idiotípicos/metabolismo , Linfócitos B/efeitos dos fármacos , Encéfalo/efeitos dos fármacos , Encéfalo/metabolismo , Encéfalo/patologia , Linhagem Celular Tumoral , Ensaio de Imunoadsorção Enzimática/métodos , Epitopos de Linfócito B/imunologia , Humanos , Neuroblastoma/patologia , Ligação Proteica/efeitos dos fármacos , Coelhos
16.
Mol Immunol ; 47(2-3): 270-82, 2009 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-19853920

RESUMO

While the antigenic variability is the major obstacle for developing vaccines against antigenically variable pathogens (AVPs) and cancer, this issue is not addressed adequately in current vaccine efforts. We developed a novel variable epitope library (VEL)-based vaccine strategy using immunogens carrying a mixture of thousands of variants of a single epitope. In this proof-of-concept study, we used an immunodominant HIV-1-derived CD8+ cytotoxic T-lymphocyte (CTL) epitope as a model antigen to construct immunogens in the form of plasmid DNA and recombinant M13 bacteriophages. We generated combinatorial libraries expressing epitope variants with random amino acid substitutions at 2-5 amino acid positions within the epitope. Mice immunized with these immunogens developed epitope-specific CD8+ IFN-gamma+ T-cell responses that recognized more than 50% of heavily mutated variants of wild-type epitope, as demonstrated in T-cell proliferation assays and FACS analysis. Strikingly, these potent and broad epitope-specific immune responses were long lasting: after 12 months of priming, epitope variants were recognized by CD8+ cells and effector memory T cells were induced. In addition, we showed, for the first time, the inhibition of T-cell responses at the molecular level by immune interference: the mice primed with wild-type epitope and 8 or 12 months later immunized with VELs, were not able to recognize variant epitopes efficiently. These data may give a mechanistic explanation for the failure of recent HIV vaccine trials as well as highlight specific hurdles in current molecular vaccine efforts targeting other important antigenically variable pathogens and diseases. These findings suggest that the VEL-based strategy for immunogen construction can be used as a reliable technological platform for the generation of vaccines against AVPs and cancer, and contribute to better understanding complex host-pathogen interactions.


Assuntos
Epitopos/imunologia , Biblioteca de Peptídeos , Vacinas Sintéticas/imunologia , Sequência de Aminoácidos , Animais , Epitopos/química , Citometria de Fluxo , Humanos , Imunidade Celular/imunologia , Imunização , Memória Imunológica/imunologia , Ativação Linfocitária/imunologia , Camundongos , Camundongos Endogâmicos BALB C , Dados de Sequência Molecular , Fenótipo
17.
Neurochem Int ; 52(6): 1030-6, 2008 May.
Artigo em Inglês | MEDLINE | ID: mdl-18079022

RESUMO

Extracellular and intraneuronal formation of amyloid-beta aggregates have been demonstrated to be involved in the pathogenesis of Alzheimer's disease. However, the precise mechanism of amyloid-beta neurotoxicity is not completely understood. Previous studies suggest that binding of amyloid-beta to a number of targets have deleterious effects on cellular functions. In the present study we have shown for the first time that amyloid-beta 1-42 bound to a peptide comprising the microtubule binding domain of the heavy chain of microtubule-associated protein 1B by the screening of a human brain cDNA library expressed on M13 phage. This interaction may explain, in part, the loss of neuronal cytoskeletal integrity, impairment of microtubule-dependent transport and synaptic dysfunction observed previously in Alzheimer's disease.


Assuntos
Doença de Alzheimer/metabolismo , Peptídeos beta-Amiloides/metabolismo , Encéfalo/metabolismo , Proteínas Associadas aos Microtúbulos/metabolismo , Neurônios/metabolismo , Fragmentos de Peptídeos/metabolismo , Encéfalo/fisiopatologia , Linhagem Celular Tumoral , Humanos , Microtúbulos/metabolismo , Peptídeos/metabolismo , Ligação Proteica/fisiologia , Estrutura Terciária de Proteína/fisiologia , Transporte Proteico/fisiologia , Transmissão Sináptica/fisiologia
18.
Clin Immunol ; 116(3): 265-70, 2005 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-15905129

RESUMO

A novel cDNA cloning strategy consisting in elimination of non-coding DNA sequences from 3' regions of cDNAs was applied to construct the Taenia crassiceps phage displayed cDNA expression library. After biopanning using immune sera, three phage clones expressing T. crassiceps-derived antigens specifically recognizing antibodies present in cerebrospinal fluid and plasma samples from neuroimaging-confirmed neurocysticercosis patients were selected. This novel cloning strategy may be applied to other pathogens allowing rapid identification of peptides/proteins for immunodiagnostic tests.


Assuntos
Antígenos de Helmintos/genética , Neurocisticercose/diagnóstico , Taenia/genética , Taenia/imunologia , Sequência de Aminoácidos , Animais , Anticorpos Anti-Helmínticos/sangue , Anticorpos Anti-Helmínticos/líquido cefalorraquidiano , Sequência de Bases , DNA Complementar/genética , DNA de Helmintos/genética , Biblioteca Gênica , Humanos , Camundongos , Neurocisticercose/imunologia , Neurocisticercose/parasitologia , Biblioteca de Peptídeos
19.
Immunol Lett ; 95(2): 207-12, 2004 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-15388262

RESUMO

The HIV-1 envelope glycoprotein gp41 contains Cys(X)5Cys motif, which has been shown to elicit a strong antibody response in almost all HIV-1 infected individuals. This disulfide-bonded loop region is conserved in most retroviruses suggesting the existence of an essential function in virus life cycle. In this study, we displayed the peptides comprising 12 amino acids of the immunodominant loop of gp41 on the surface of M13 phage as N-terminal fusions to the minor coat protein pIII and major coat protein pVIII of the phage and demonstrated that cysteine loop containing peptide expressed on phage recognized 62 out of 63 (98.4%) HIV-1 positive samples but not control negative sera while phage bearing linear peptides detected 4-30% of HIV-1-positive sera. The main advantage of phage-based ELISA or other antibody detection-based diagnostic tests of HIV-infection to be used for massive screening in developing countries is the reproducible, simple, rapid and low-cost production of recombinant antigens.


Assuntos
Dissulfetos/química , Antígenos HIV/imunologia , Proteína gp41 do Envelope de HIV/química , Proteína gp41 do Envelope de HIV/imunologia , Biblioteca de Peptídeos , Ligação Competitiva , Dissulfetos/imunologia , Ensaio de Imunoadsorção Enzimática , Anticorpos Anti-HIV/imunologia , Antígenos HIV/química , Proteína gp41 do Envelope de HIV/genética , Infecções por HIV/sangue , Infecções por HIV/imunologia , HIV-1/imunologia , Humanos , Epitopos Imunodominantes/química , Epitopos Imunodominantes/imunologia , Mercaptoetanol/farmacologia , Substâncias Redutoras/farmacologia , Sensibilidade e Especificidade
20.
Gac. méd. Méx ; 134(4): 385-96, jul.-ago. 1998. ilus, tab
Artigo em Espanhol | LILACS | ID: lil-232770

RESUMO

El presente trabajo explora la digitalización de imágenes de "western blot" (WB) para extraer mayor información acerca de la respuesta inmune humoral del paciente infectado por el virus de la inmunodeficiencia adquirida humana (VIH) y analizar de manara multivariada los datos obtenidos. Se realizó la digitalización y análisis de las imágenes de WB de 115 sueros. Con estos datos se hicieron análisis tanto cualitativos: dendograma y análisis de componentes principales (ACP), como cuantitativos: ACP con el total de bandas tomando sólo los antígenos propios del virus o utilizando los antígenos que no pertenecen al virus. Los resultados demuestran la factibilidad de diagnosticar de forma mecánica un número grande de imágenes de WB. Tanto el dendograma como el ACP cualitativo separaron, de manera adecuada, imágenes blancas, imágenes con menos de cuatro bandas e imágenes con patrones más complejos. El análisis cuantitativo, que conserva más información, separa perfectamente imágenes de diagnóstico negativo, indeterminado y positivo. Además, se encontró que las imágenes con patrones complejos correlacionan más con individuos asintomáticos. Este análisis reveló también la existencia de banda que no parecen corresponder a proteínas virales, mismas que pudieran corresponder a autoantígenos o antígenos cruzados entre el VIH y el ser humano, dando cauce a autoinmunidad. El análisis digital de imágenes de WB en el caso del VIH, prueba así su gran utilidad en el diagnóstico de caso y en el seguimiento de la evolución y patogenia de la enfermedad


Assuntos
Humanos , Western Blotting , Sorodiagnóstico da AIDS/métodos
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