Publications by authors named "Ana K Oliveira"

Article Synopsis
  • Viperid snake venoms cause significant tissue damage through direct toxicity and inflammatory responses, primarily involving phospholipases A and metalloproteinases.
  • A study utilized Nanostring technology to analyze gene expression in mouse skeletal muscle at different time points post-venom injection, revealing diverse patterns related to extracellular matrix metabolism, immune responses, and cell death processes.
  • Results indicated a complex interplay of gene regulation, with certain genes up-regulated (e.g., those linked to fibrosis and inflammatory processes) and others down-regulated, shedding light on the pathological events triggered by snake venom exposure.
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Introduction: Neuronal nuclei are normally smoothly surfaced. In Alzheimer's disease (AD) and other tauopathies, though, they often develop invaginations. We investigated mechanisms and functional consequences of neuronal nuclear invagination in tauopathies.

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Extracellular vesicles (EVs) are biomolecule carriers for intercellular communication in health and disease. Nef is a HIV virulence factor that is released from cells within EVs and is present in plasma EVs of HIV-1 infected individuals. We performed a quantitative proteomic analysis to fully characterize the Nef-induced changes in protein composition of T cell-derived EVs and identify novel host targets of HIV.

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Snakebite envenomation is classified as a Neglected Tropical Disease. Bothrops jararaca venom induces kidney injury and coagulopathy. HF3, a hemorrhagic metalloproteinase of B.

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Hemorrhage induced by snake venom metalloproteases (SVMPs) results from proteolysis, capillary disruption, and blood extravasation. HF3, a potent SVMP of Bothrops jararaca, induces hemorrhage at pmol doses in the mouse skin. To gain insight into the hemorrhagic process, the main goal of this study was to analyze changes in the skin peptidome generated by injection of HF3, using approaches of mass spectrometry-based untargeted peptidomics.

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Introduction: Neuronal nuclei are normally smoothly surfaced. In Alzheimer's disease (AD) and other tauopathies, though, they often develop invaginations. We investigated mechanisms and functional consequences of neuronal nuclear invagination in tauopathies.

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Cancer is a significant cause of death, precluding increasing life expectancy worldwide. That is a multifactorial disease initiated by intrinsic or extrinsic factors that induce cell differentiation into cancer cells. However, cancer development, progression, and metastasis are not controlled only by cancer cells.

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Pathological and inflammatory events in muscle after the injection of snake venoms vary in different regions of the affected tissue and at different time intervals. In order to study such heterogeneity in the immune cell microenvironment, a murine model of muscle necrosis based on the injection of the venom of was used. Histological and immunohistochemical methods were utilized to identify areas in muscle tissue with a different extent of muscle cell damage, based on the presence of hypercontracted muscle cells, a landmark of necrosis, and on the immunostaining for desmin.

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Hemorrhage induced by snake venom metalloproteinases (SVMPs) is a complex phenomenon that involves capillary disruption and blood extravasation. HF3 (hemorrhagic factor 3) is an extremely hemorrhagic SVMP of venom. Studies using proteomic approaches revealed targets of HF3 among intracellular and extracellular proteins.

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Patients bitten by snakes consistently manifest a bleeding tendency, in which thrombocytopenia, consumption coagulopathy, mucous bleeding, and, more rarely, thrombotic microangiopathy, are observed. Von Willebrand factor (VWF) is required for primary hemostasis, and some venom proteins, such as botrocetin (a C-type lectin-like protein) and snake venom metalloproteinases (SVMP), disturb the normal interaction between platelets and VWF, possibly contributing to snakebite-induced bleedings. To understand the relationship among plasma VWF, platelets, botrocetin and SVMP from Bothrops jararaca snake venom (BjV) in the development of thrombocytopenia, we used (a) Wistar rats injected s.

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Oral squamous cell carcinoma (OSCC) has high mortality rates that are largely associated with lymph node metastasis. However, the molecular mechanisms that drive OSCC metastasis are unknown. Extracellular vesicles (EVs) are membrane-bound particles that play a role in intercellular communication and impact cancer development and progression.

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Article Synopsis
  • * There is a pressing need for new biomarkers and therapeutic targets to improve clinical decision-making, with ongoing proteomic studies exploring the tumor environment and potential liquid biopsy sites for OSCC.
  • * Although proteomics shows promise in identifying candidates for biomarkers and treatments, these targets have not yet made it into clinical practice, indicating the need for better experimental designs and translation of research into actionable clinical strategies.
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Protease activity has been associated with pathological processes that can lead to cancer development and progression. However, understanding the pathological unbalance in proteolysis is challenging because changes can occur simultaneously at protease, their inhibitor, and substrate levels. Here, we present a pipeline that combines peptidomics, proteomics, and peptidase predictions for studying proteolytic events in the saliva of 79 patients and their association with oral squamous cell carcinoma (OSCC) prognosis.

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Most characterized angiogenic modulators are proteolytic fragments of structural plasma and/or matrix components. Herein, we have identified a novel anti-angiogenic peptide generated by the hydrolysis of the C-terminal moiety of the fibrinogen alpha chain, produced by the snake venom metalloprotease bothropasin (SVMP), a hemorrhagic proteinase in Bothrops jararaca venom. The 14-amino acids peptide (alphastatin-C) is a potent antagonist of basic fibroblast growth factor, induced endothelial cell (HUVEC-CS) proliferation, migration and capillary tube formation in matrigel.

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Article Synopsis
  • Envenoming from viper snakes causes tissue damage and hemorrhage, with snake venom metalloproteinases (SVMPs) playing a key role in this process.
  • Hemorrhagic Factor 3 (HF3), a specific SVMP, causes severe local hemorrhage in animal models by interacting with various proteins and proteoglycans.
  • The study reveals that HF3 not only degrades proteoglycans but also cleaves important proteins like platelet-derived growth factor receptor (PDGFR), highlighting the complex mechanisms of tissue damage caused by SVMPs and their effects on microvascular integrity.
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Snakebite is a major medical concern in many parts of the world with metalloproteases playing important roles in the pathological effects of Viperidae venoms, including local tissue damage, hemorrhage, and coagulopathy. Hemorrhagic Factor 3 (HF3), a metalloprotease from venom, induces local hemorrhage and targets extracellular matrix (ECM) components, including collagens and proteoglycans, and plasma proteins. However, the full substrate repertoire of this metalloprotease is unknown.

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Manifestations of local tissue damage, such as hemorrhage and myonecrosis, are among the most dramatic effects of envenomation by viperid snakes. Snake venom metalloproteinases (SVMPs) of the P-III class are main players of the hemorrhagic effect due to their activities in promoting blood vessel disruption. Hemorrhagic Factor 3 (HF3), a P-III class SVMP from Bothrops jararaca, shows a minimum hemorrhagic dose of 240 fmol on rabbit skin.

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Leptospires are highly motile spirochetes equipped with strategies for efficient invasion and dissemination within the host. Our group previously demonstrated that pathogenic leptospires secrete proteases capable of cleaving and inactivating key molecules of the complement system, allowing these bacteria to circumvent host's innate immune defense mechanisms. Given the successful dissemination of leptospires during infection, we wondered if such proteases would target a broader range of host molecules.

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Over the years, several tumor biomarkers have been suggested to foresee the prognosis oral squamous cell carcinoma (OSCC) patients. Here, we present a systematic review to identify, evaluate and summarize the evidence for OSCC reported markers. Eligible studies were identified through a literature search of MEDLINE/PubMed until January 2016.

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Viperid snake venoms contain proteases that affect hemostasis by degrading important proteins such as those that participate in the coagulation cascade. The Bothrops jararaca venom presents as its main components metallo and serine proteases, which comprise around 65% of the venom composition. Bothropasin is a hemorrhagic metalloprotease from the B.

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Paracoccidioides brasiliensis, a thermally dimorphic fungus, is the causative agent of paracoccidioidomycosis, a systemic mycosis that is widespread in Latin America. This fungus is a facultative intracellular pathogen able to survive and replicate inside non-activated macrophages. Therefore, the survival of P.

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The Proteomic Identification of Cleavage Sites (PICS) approach was employed for profiling the substrate specificity of HF3, a hemorrhagic snake venom metalloproteinase (SVMP) from Bothrops jararaca. A tryptic peptide library from human plasma was subject to HF3 cleavage and amino acid occurrence for P6 to P6' sites was mapped. 71 cleavage sites were detected and revealed a clear preference for leucine at P1' position, followed by hydrophobic residues in P2'.

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Unlabelled: Many snake venom toxins are serine proteases but their specific in vivo targets are mostly unknown. Various act on components of the coagulation cascade, and fibrinolytic and kallikrein-kinin systems to trigger various pathological effects observed in the envenomation. Despite showing high similarity in terms of primary structure snake venom serine proteinases (SVSPs) show exquisite specificity towards macromolecular substrates.

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