Publications by authors named "Maria L Oliva"

Proteinase inhibitors have been associated with anti-inflammatory and antioxidant activities and may represent a potential therapeutic treatment for emphysema. Our aim was to evaluate the effects of a plant Kunitz proteinase inhibitor, trypsin inhibitor (EcTI), on several aspects of experimental elastase-induced pulmonary inflammation in mice. C57/Bl6 mice were intratracheally administered elastase (ELA) or saline (SAL) and were treated intraperitoneally with EcTI (ELA-EcTI, SAL-EcTI) on days 1, 14 and 21.

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Cancer progression is associated with an evolving tissue interface of direct epithelial-tumor microenvironment interactions. In biopsies of human breast tumors, extensive alterations in molecular pathways are correlated with cancer staging on both sides of the tumor-stroma interface. These interactions provide a pivotal paracrine signaling to induce malignant phenotype transition, the epithelial-mesenchymal transition (EMT).

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Unlabelled: Lectins have been used at length for basic research and clinical applications. New insights into the molecular recognition properties enhance our basic understanding of carbohydrate-protein interactions and aid in the design/development of new lectins. In this study, we used a combination of cell-based assays, glycan microarrays, and X-ray crystallography to evaluate the structure and function of the recombinant Bauhinia forficata lectin (BfL).

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Background. Elastase mediates important oxidative actions during the development of chronic obstructive pulmonary disease (COPD). However, few resources for the inhibition of elastase have been investigated.

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Cell culture is considered the standard media used in research to emulate the in vivo cell environment. Crucial in vivo experiments cannot be conducted in humans and depend on in vitro methodologies such as cell culture systems. However, some procedures involving the quality control of cells in culture have been gradually neglected by failing to acknowledge that primary cells and cell lines change over time in culture.

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Background: Breast cancer comprises clinically and molecularly distinct tumor subgroups that differ in cell histology and biology and show divergent clinical phenotypes that impede phase III trials, such as those utilizing cathepsin K inhibitors. Here we correlate the epithelial-mesenchymal-like transition breast cancer cells and cathepsin K secretion with activation and aggregation of platelets. Cathepsin K is up-regulated in cancer cells that proteolyze extracellular matrix and contributes to invasiveness.

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Callosobruchus maculatus is an important predator of cowpeas. Due to infestation during storage, this insect affects the quality of seed and crop yield. This study aimed to investigate the effects of CrataBL, a multifunction protein isolated from Crataeva tapia bark, on C.

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During the epileptogenic process, several events may occur, such as an important activation of the immune system in the central nervous system. The response to seizure activity results in an inflammation in the brain as well as in the periphery. Moreover, CRP and cytokines may be able to interact with numerous ligands in response to cardiac injury caused by sympathetic stimulation in ictal and postictal states.

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A serine protease inhibitor from Bauhinia bauhinioides (BbKI) belongs to the Kunitz family of plant inhibitors, which are common in plant seeds. BbKI does not contain any disulfides, unlike most other members of this family. It is a potent inhibitor of plasma kallikrein, in addition to other serine proteases, and thus exhibits antithrombotic activity.

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Proteinase inhibitors extracted form medicinal plants are an interesting source of new drugs. Modifications in the structure of some of this kind of macromolecules could also lead to compounds of interesting biological properties. In this work, we synthesized and tested one fragment containing the reactive site of the Bauhinia bauhinioides kallikrein inhibitor (BbKI), denoted BbKI51-62 , and a related analog (P2 ) in which a proline residue was inserted in order to mimic the N-terminal region of the bradykinin molecule.

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Arterial thrombosis is an important complication of diabetes and cancer, being an important target for therapeutic intervention. Crataeva tapia bark lectin (CrataBL) has been previously shown to have hypoglycemiant effect and also to induce cancer cell apoptosis. It also showed inhibitory activity against Factor Xa (Kiapp=8.

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The Bauhinia bauhinioides Kallikrein Inhibitor (BbKI) is a Kunitz-type serine peptidase inhibitor of plant origin that has been shown to impair the viability of some tumor cells and to feature a potent inhibitory activity against human and rat plasma kallikrein (Kiapp 2.4 nmol/L and 5.2 nmol/L, respectively).

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Background: Plant lectins have attracted great interest in cancer studies due to their antitumor activities. These proteins or glycoproteins specifically and reversibly bind to different types of carbohydrates or glycoproteins. Breast cancer, which presents altered glycosylation of cell surface glycoproteins, is one of the most frequent malignant diseases in women.

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Baupain belongs to the α+β class of proteins with a secondary structure-content of 44% α-helix, 16% β-sheet and 12% β-turn. The structural transition induced by pH was found to be noncooperative, with no important differences observed in the pH range from 3.0 to 10.

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One of the many control mechanisms of serine proteinases is their specific inhibition by protein proteinase inhibitors. An extract of Acacia schweinfurthii was screened for potential serine proteinase inhibition. It was successfully purified to homogeneity by precipitating with 80% (v/v) acetone and sequential chromatographic steps, including ion-exchange, affinity purification and reversed-phase high performance liquid chromatography.

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A protein isolated from the bark of Crataeva tapia (CrataBL) is both a Kunitz-type plant protease inhibitor and a lectin. We have determined the amino acid sequence and three-dimensional structure of CrataBL, as well as characterized its selected biochemical and biological properties. We found two different isoforms of CrataBL isolated from the original source, differing in positions 31 (Pro/Leu); 92 (Ser/Leu); 93 (Ile/Thr); 95 (Arg/Gly) and 97 (Leu/Ser).

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A serine protease inhibitor from Enterolobium contortisiliquum (EcTI) belongs to the Kunitz family of plant inhibitors, common in plant seeds. It was shown that EcTI inhibits the invasion of gastric cancer cells through alterations in integrin-dependent cell signaling pathway. We determined high-resolution crystal structures of free EcTI (at 1.

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Lectins are carbohydrate recognition proteins. cMoL, a coagulant Moringa oleifera Lectin, was isolated from seeds of the plant. Structural studies revealed a heat-stable and pH resistant protein with 101 amino acids, 11.

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Background: Kallikreins play a pivotal role in establishing prostate cancer.

Results: In contrast to the classical Kunitz plant inhibitor SbTI, the recombinant kallikrein inhibitor (rBbKIm) led to prostate cancer cell death, whereas fibroblast viability was not affected.

Conclusion: rBbKIm shows selective cytotoxic effect and angiogenesis inhibition against prostate cancer cells.

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CrataBL, a protein isolated from Crataeva tapia bark, which is both a serine protease inhibitor and a lectin, has been previously shown to exhibit a number of interesting biological properties, including anti-inflammatory, analgesic, antitumor, and insecticidal activities. Using a glycan array, we have now shown that only sulfated carbohydrates are effectively bound by CrataBL. Because this protein was recently shown to delay clot formation by impairing the intrinsic pathway of the coagulation cascade, we considered that its natural ligand might be heparin.

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As Aedes aegypti transmits the etiologic agents of both yellow and dengue fever; vector control is considered essential to minimise their incidence. The aim of this work was to identify the component of Carica papaya seed toxic to A. aegypti, and the identification of tegupain, the enzyme that generates it.

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In cancer tumors, growth, invasion, and formation of metastasis at a secondary site play a pivotal role, participating in diverse processes in the development of the pathology, such as degradation of extracellular matrix. Bauhinia seeds contain relatively large quantities of peptidase inhibitors, and two Bauhinia inhibitors were obtained in a recombinant form from the Bauhinia bauhinioides species, B. bauhinoides cruzipain inhibitor, which is a cysteine and serine peptidase inhibitor, and B.

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BbKI is a kallikrein inhibitor with a reactive site sequence similar to that of kinins, the vasoactive peptides inserted in kininogen moieties. This structural similarity probably contributes to the strong interaction with plasma kallikrein, the enzyme that releases, from high-molecular weight kininogen (HMWK), the proinflammatory peptide bradykinin, which acts on B(2) receptors (B(2)R). BbKI was examined on smooth muscle contraction and Ca(2+) mobilization, in which the kallikrein-kinin system is involved.

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Passion fruit (Passiflora edulis Sims f. flavicarpa) is popularly known for its sedative and calming properties and is consumed as a fresh fruit or as a juice. The clinical observation of blood incoagulability associated with excessive consumption of passion fruit juice, in a patient treated with warfarin, prompted the current study to investigate in vitro the presence of blood clotting inhibitors in Passiflora edulis Sims f.

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Hemagglutinating activity has been associated to presence of lectin, carbohydrate-binding proteins. In this work Crataeva tapia bark lectin (CrataBL) was purified in milligram quantities (28 mg per g of bark) by ion exchange chromatography. The lectin was thermo-stable, ion-independent and N-terminal sequence analysis demonstrated similarity with miraculin and miraculin-like proteins (plant defensive proteins).

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