Descripción inmunohistoquímica de la encefalitis en bovinos brasileños naturalmente infectados con el herpesvirus bovino tipo 5 (HVB-5)

Twelve cases of viral meningoencephalitis in Brazilian cattle were submitted to immunohistochemical analysis for inflammatory response description. All the cases showed severe neurological signs followed by death. Mild to moderate histological inflammatory changes in the brain and cerebellum characterized the neurological infection showing meningitis, mononuclear perivascular cuffing, gliosis, haemorrhage, and macrophages (gitter cells) accompanying great areas of malacia. None of the cases showed intranuclear inclusion bodies. However, in five of them it was possible to isolate the BoHV-5. In order to collect data to allow the description of the inflammatory response in these cases, brain samples from all of the cases were analyzed by immunohistochemistry using polyclonal antibodies against CD3 to detect T cells, and against GFAP to detect astrocytes. On the other hand, monoclonal antibodies were used against BLA to detect B cells and, against MAC 387 to detect macrophages. The results indicate different degrees of prominent astrocytic response, and at the same time, T lymphocytes constituted a high percentage of the mononuclear cells which characterized the inflammatory response.

Inhibition of human neutrophil apoptosis by Paracoccidioides brasiliensis: Role of interleukin-8

Paracoccidioidomycosis (PCM) is a systemic mycosis caused by Paracoccidiodes brasiliensis that presents a wide spectrum of clinical manifestations. Because of the great number of neutrophils polymorphonuclear neutrophils (PMN) found in the P. brasiliensis granuloma, studies have been done to evaluate the role of these cells during the development of the infection. This fungus is found intracellularly in PMN and monocytes/macrophages, suggesting that it is capable of evading damage and surviving inside these cells. Thus, in the present study, we investigated whether P. brasiliensis can prolong the lifetime of PMN, and if this process would be related with IL-8 levels. PMN apoptosis and intracellular levels of IL-8 were analysed by flow cytometry and culture supernatants IL-8 levels were evaluated by enzyme-linked immunosorbent assay. We found that coincubation with P. brasiliensis yeast cells results in an inhibition of PMN apoptosis, which was associated with increase in IL-8 production by these cells. Cocultures treatment with monoclonal antibody anti-IL-8 reversed the inhibitory effect of P. brasiliensis on PMN apoptosis, besides to increase spontaneous apoptosis of these cells. These data show that, in contrast to other microbial pathogens that drive phagocytes into apoptosis to escape killing, P. brasiliensis can extend the lifetime of normal human PMN by inducing autocrine IL-8 production. © 2008 The Authors.

DNA vaccine containing the mycobacterial hsp65 gene prevented insulitis in MLD-STZ diabetes

Background: Our group previously demonstrated that a DNA plasmid encoding the mycobacterial 65-kDa heat shock protein (DNA-HSP65) displayed prophylactic and therapeutic effect in a mice model for tuberculosis. This protection was attributed to induction of a strong cellular immunity against HSP65. As specific immunity to HSP60 family has been detected in arthritis, multiple sclerosis and diabetes, the vaccination procedure with DNA-HSP65 could induce a cross-reactive immune response that could trigger or worsen these autoimmune diseases. Methods: In this investigation was evaluated the effect of a previous vaccination with DNA-HSP65 on diabetes development induced by Streptozotocin (STZ). C57BL/6 mice received three vaccine doses or the corresponding empty vector and were then injected with multiple low doses of STZ. Results: DNA-HSP65 vaccination protected mice from STZ induced insulitis and this was associated with higher production of IL-10 in spleen and also in the islets. This protective effect was also concomitant with the appearance of a regulatory cell population in the spleen and a decreased infiltration of the islets by T CD8+ lymphocytes. The vector (DNAv) also determined immunomodulation but its protective effect against insulitis was very discrete. Conclusion: The data presented in this study encourages a further investigation in the regulatory potential of the DNA-HSP65 construct. Our findings have important implications for the development of new immune therapy strategies to combat autoimmune diseases. © 2009 Santos et al; licensee BioMed Central Ltd.

Acute coronary syndrome associated with continuous 5-fluorouracil infusion in a patient with metastatic colorectal cancer-a case report with a discussion on this clinical dilemma

Introduction: 5-Fluorouracil (5-FU) is considered to be the backbone of colorectal cancer (CRC) systemic therapy since the great majority of recommended regimens include its administration. A clinical picture consisting of chest pain, sometimes cardiac enzyme elevation, electrocardiogram abnormalities consistent with myocardial ischemia, and normal coronary angiogram associated with 5-FU administration have been infrequently reported. The clinical dilemma is: Which chemotherapy regimen should we use in CRC patients with a previous acute coronary syndrome (ACS) associated with 5-FU? Case Report: We describe the case of a 55-year-old otherwise healthy woman with metastatic colon adenocarcinoma who presented an ACS probably secondary to arterial vasospasm while receiving continuous intravenous 5-FU infusion (mFOLFOX6 regimen). After the ACS, the patient was treated with raltitrexate plus oxaliplatin (TOMOX) and subsequently with irinotecan plus cetuximab with no other cardiac event. Conclusion: The risk of cardiotoxicity associated with 5-FU is low but real. The probable mechanism is arterial vasospasm, as suggested by our case report. Both the use of the TOMOX regimen and irinotecan plus cetuximab seems to be safe regimens to be considered in this clinical scenario. © 2009 Humana Press Inc.

Acute phase proteins in canine lymphoma during antineoplastic chemotherapy

The lymphoma is the main hematopoietic tumor in dogs and it is characterized by the proliferation of cells from lymphoid tissue, histiocytes and its precursors. Animals with lymphoma often show changes in biochemical and hematological parameters such as non-regenerative normochromic normocytic anemia, hemolytic anemia, hypocalcaemia and monoclonal gammopathy. The development of tumor can cause alterations in serum concentrations of acute phase proteins (APPs), consequent of hepatocytes stimulus by cytokines of inflammatory action. This study aimed to quantify and qualify APPs in dogs with lymphoma, at diagnosis time and during the time of chemotherapy sessions. After syneresis, centrifugation and fractioning the serum samples of 10 healthy and 10 dogs with lymphomas, the proteins fractions were separated by polyacrilamide gel electrophoresis (SDS-PAGE) and its concentrations were determined by computer densitometry. Between 18 and 30 proteins were separated by eletrophoresis, with molecular weights ranging from 18 to 245 kDa (kilodaltons). The alpha-1-glicoprotein acid (AGP) and transferrin serum concentration showed significantly higher in dogs with lymphoma, when compared with healthy dogs at diagnosis. The alpha-1-antitripsin (AAT) serum concentrations showed significantly higher in healthy dogs, when compared with dogs with lymphoma at diagnosis. The dogs with lymphoma the albumin did not appear as negative APP. On the other hand, transferrin appeared as positive AAP at diagnosis time and during the chemotherapy sessions. Healthy dogs had AAT serum concentrations significantly higher when compared to dogs with lymphoma at diagnosis. So, in this trial, it is suggested that this protein has been shown as a negative APP in the dogs with lymphoma. These dogs presented significantly higher AGP serum concentrations, in relation to healthy dogs at diagnosis, evidencing this protein APP positive behavior in neoplasm.

Expression of p53, Ki-67, and CD31 proteins in endometrial polyps of postmenopausal women treated with tamoxifen.

This study was undertaken to investigate the expression of p53, Ki-67, and CD31 proteins in endometrial polyps of postmenopausal women treated with tamoxifen (TAM). Postmenopausal women with endometrial polyps treated with TAM (n = 20), postmenopausal women with endometrial polyps without hormone use (n = 20), postmenopausal women with atrophic endometrium (n = 20), and postmenopausal women with endometrial adenocarcinoma (n = 20) were prospectively investigated. Tissue samples were immunohistochemically evaluated by monoclonal antibodies for p53, Ki-67, and CD31. The data were analyzed using the Student t test, analysis of variance, and χ2 to evaluate significant differences between the groups. The level of significance was set at P < 0.05. There was no difference in the expression of p53 between the groups (P = 0.067). The expression of Ki-67 was higher in the polyp samples from TAM-treated women compared with those from the women using no hormone (P = 0.0047) and those from the women with atrophic endometrium (P = 0.008). Samples from the women with endometrial cancer was associated with higher Ki-67 expression compared with the polyp samples from TAM-treated women (P = 0.004). The expression of CD31 was higher in the polyp samples of TAM-treated women compared with that of the samples from the women with atrophic endometrium (P < 0.001) and similar to the polyp samples from the women using no hormone (P = 0.319) and to the samples from the women with endometrial cancer (P = 0.418). The use of TAM in postmenopausal women might be associated with increased cellular proliferation in endometrial polyps without interfering angiogenesis or inactivation of tumor suppressor proteins.

Aparecimento de psoríase durante o tratamento das doenças inflamatórias intestinais com infliximabe: A terapia biológica deve ser suspensa?

Context - Several paradoxical cases of infliximab-induced or-exacerbated psoriatic lesions have been described in the recent years. There is disagreement regarding the need to discontinue infliximab in order to achieve the resolution of these adverse cutaneous reactions specifically in inflammatory bowel disease (IBD) patients. Objective - To systematically review the literature to collect information on IBD patients that showed this adverse cutaneous reaction, focusing mainly on the therapeutic approach. Methods - A systematic literature review was performed utilizing Medline, Embase, SciELO and Lilacs databases. Published studies were identified, reviewed and the data were extracted. Results - Thirty-four studies (69 IBD patients) met inclusion criteria for review. There was inconsistency in reporting of some clinical and therapeutic aspects. Most patients included had Crohn's disease (89.86%), was female (47.83%), had an average age of 27.11 years, and no reported history of psoriasis (84.05%). The patients developed primarily plaque-type psoriasis (40.58%). There was complete remission of psoriatic lesions in 86.96% of IBD patients, existing differences in the therapeutic approaches; cessation of infliximab therapy led to resolution in 47.83% of cases and 43.48% of patients were able to continue infliximab therapy. Conclusion - As increasing numbers of IBD patients with psoriasis induced or exacerbated by infliximab, physicians should be aware of its clinical manifestations so that appropriate diagnosis and treatment are properly established. The decision whether to continue or discontinue infliximab should be individualized.

Immunophenotyping of thymic lymphoma in a Nelore cow

Thymic lymphoma is a malignant lymphoid neoplasm that affects several species, including cattle. This type of neoplasia can lead to death due to malignant cell infiltration in different organs. The classification of this neoplasm may predict prognosis and response to treatment. Immunophenotyping is one of the ways to perform this classification. There are reports about the performance of immunohistochemistry (IHC) to classify thymic lymphoma only in taurine cattle, therefore the aim of this report is to describe the immunophenotype of a thymic lymphoma in a Nelore cow. Immunostaining was performed with monoclonal antibodies (CD79, CD4 and CD8). The tumor cells showed positive staining only for CD8 T lymphocytes, coinciding with the disease progression, since the T lymphoma type is more aggressive.

Comparative study of the behavior of p53 immunoexpression in smoking associated lesions: Reinke's edema and laryngeal carcinoma

Objective: To assess the behavior of the immunoexpression of protein p53 in Reinke's edema and laryngeal squamous cell carcinoma. Study design: retrospective. Methods: we recovered the histological paraffin blocks of patients who were subjected to Reinke's edema and laryngeal squamous cell carcinoma surgery in 2000-2011. The paraffin blocks were cut into 3-μm sections; the specimens were prepared in silanized slides (one slide for each paraffin block) and subjected to immunohistochemical reaction according to the Avidin Biotin Peroxidase method. Monoclonal primary anti-p53 antibodies were used at 1:50 dilution. Slides were examined under a light microscope at different magnitudes and results were interpreted based on the degree of brown staining in the nuclei of epithelial cells and in the extent of the fragment by using a semi-quantitative score from 0 to 3. Results: 67 slides of Reinke's edema and 60 slides of laryngeal squamous cell carcinoma were included. Scores 2 and 3 for staining of the nuclei of epithelial cells were recorded for 46 slides of Reinke's edema (68.65%) and for 57 slides of laryngeal squamous cell carcinoma (95%). As to the extent of the fragment, scores 2 and 3 were recorded for 74% slides of Reinke's edema and for 95% slides of carcinomas. Conclusion: the positive immunoexpression for protein p53, positive in 95% carcinomas and 74% Reinke's edemas, makes us aware of the possible preneoplastic condition of the latter lesion. Further studies are needed to identify and reveal the genetic changes that lead to these results. © 2013 Informa Healthcare USA, Inc.

Infliximab prevents increased systolic blood pressure and upregulates the AKT/eNOS pathway in the aorta of spontaneously hypertensive rats

High systolic blood pressure caused by endothelial dysfunction is a comorbidity of metabolic syndrome that is mediated by local inflammatory signals. Insulin-induced vasorelaxation due to endothelial nitric oxide synthase (eNOS) activation is highly dependent on the activation of the upstream insulin-stimulated serine/threonine kinase (AKT) and is severely impaired in obese, hypertensive rodents and humans. Neutralisation of circulating tumor necrosis factor-α (TNFα) with infliximab improves glucose homeostasis, but the consequences of this pharmacological strategy on systolic blood pressure and eNOS activation are unknown. To address this issue, we assessed the temporal changes in the systolic pressure of spontaneously hypertensive rats (SHR) treated with infliximab. We also assessed the activation of critical proteins that mediate insulin activity and TNFα-mediated insulin resistance in the aorta and cardiac left ventricle. Our data demonstrate that infliximab prevents the upregulation of both systolic pressure and left ventricle hypertrophy in SHR. These effects paralleled an increase in AKT/eNOS phosphorylation and a reduction in the phosphorylation of inhibitor of nuclear factor-κB (Iκβ) and c-Jun N-terminal kinase (JNK) in the aorta. Overall, our study revealed the cardiovascular benefits of infliximab in SHR. In addition, the present findings further suggested that the reduction of systolic pressure and left ventricle hypertrophy by infliximab are secondary effects to the reduction of endothelial inflammation and the recovery of AKT/eNOS pathway activation. © 2012 Elsevier B.V.

Low RKIP expression associates with poor prognosis in bladder cancer patients

Urothelial bladder cancer (UBC) is a heterogeneous type of disease. It is urgent to screen biomarkers of tumour aggressiveness in order to clarify the clinical behaviour and to personalize therapy in UBC patients. Raf kinase inhibitory protein (RKIP) is a metastasis suppressor, and its downregulation is associated with metastatic events in an increasing number of solid tumours. We evaluated the clinical and prognostic significance of RKIP expression in patients with high risk of progression UBC. Using immunohistochemistry, we determined RKIP expression levels in a series of 81 patients with high-grade pT1/pTis or muscle-invasive UBC. Staining of CD31 and D2-40 was used to assess blood and lymphatic vessels, in order to distinguish between blood and lymphatic vessel invasion (LVI). We found that 90 % of pT1/pTis tumours, 94 % of non-muscle invasive papillary tumours and 76 % of the cases without LVI occurrence expressed RKIP in >10 % of cells. In this group, we observed a subgroup of tumours (42 %) in which the tumour centre was significantly more intensely stained than the invasion front. This heterogeneous pattern was observed in 63 % of the cases with LVI. Low RKIP expression was associated with poorer 5-year disease-free and overall survival rates, and remained as an independent prognostic factor for disease-free survival. Loss of RKIP expression may be an important prognostic factor for patients with high risk of progression bladder cancer. © 2013 Springer-Verlag Berlin Heidelberg.

Organosilylated complex [Eu(TTA)3(Bpy-Si)]: A bifunctional moiety for the engeneering of luminescent silica-based nanoparticles for bioimaging

A new highly luminescent europium complex with the formula [Eu(TTA) 3(Bpy-Si)], where TTA stands for the thenoyltrifluoroacetone, (C 4H3S)COCH2COCF3, chelating ligand and Bpy-Si, Bpy-CH2NH(CH2)3Si(OEt)3, is an organosilyldipyridine ligand displaying a triethoxysilyl group as a grafting function has been synthesized and fully characterized. This bifunctional complex has been grafted onto the surface of dense silica nanoparticles (NPs) and on mesoporous silica microparticles as well. The covalent bonding of [Eu(TTA)3(Bpy-Si)] inside uniform Stöber silica nanoparticles was also achieved. The general methodology proposed could be applied to any silica matrix, allowed high grafting ratios that overcome chelate release and the tendency to agglomerate. Luminescent silica-based nanoparticles SiO2-[Eu(TTA)3(Bpy-Si)], with a diameter of 28 ± 2 nm, were successfully tested as a luminescent labels for the imaging of Pseudomonas aeruginosa biofilms. They were also functionalized by a specific monoclonal antibody and subsequently employed for the selective imaging of Escherichia coli bacteria. © 2013 American Chemical Society.

Efeito da interleucina-15 sobre a atividade fungicida, metabolismo oxidativo e produção de citocinas por monócitos humanos, infectados in vitro com Paracoccidioides brasiliensis

Coordenação de Aperfeiçoamento de Pessoal de Nível Superior (CAPES)

Análise do desempenho da técnica de clonagem celular por micromanipulação versus diluição limitante

Conselho Nacional de Desenvolvimento Científico e Tecnológico (CNPq)

Anticorpos monoclonais em imunohematologia

Pós-graduação em Pesquisa e Desenvolvimento (Biotecnologia Médica) - FMB