The Experts below are selected from a list of 171 Experts worldwide ranked by ideXlab platform
John C. Perez - One of the best experts on this subject based on the ideXlab platform.
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Comparative study on hemorrhagic and proteolytic activities of snake venoms.
Toxicon, 2002Co-Authors: Shyi Yi Huang, John C. PerezAbstract:Abstract The hemorrhagic and proteolytic titers of nine snake venoms were measured. Suitable venom dilutions were selected to study the antihemorrhagic and Antiproteolytic activities of three warm-blooded animal sera — gray woodrat (Neotoma micropus), hispidus cottonrat (Sigmodon hispidus) and Virginia opossum (Didelphis virginiana). It was demonstrated that all hemorrhagic venoms are proteolytic. The results show that the hemorrhagic activity of the venoms is readily neutralized by the sera; however, the proteolytic activity is not neutralized. We suggest that the mechanisms involved in neutralizing the two activities are not closely related.
Paulo A. Melo - One of the best experts on this subject based on the ideXlab platform.
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Synthesis and pharmacological evaluation of prenylated and benzylated pterocarpans against snake venom
Bioorganic & Medicinal Chemistry Letters, 2004Co-Authors: Alcides J. M. Da Silva, Antonio L. Coelho, Raphael A. M. Moraes, Diogo Pinheiro, Emerson Z. Arruda, Fabrício F.a. Fernandes, Alessandro B. C. Simas, Paulo R R Costa, Paulo A. MeloAbstract:Edunol (3), a pterocarpan isolated from Harpalyce brasiliana, a plant used in the northeast of Brazil against snakebites, was obtained by synthesis and showed antimyotoxic, Antiproteolytic and PLA2 inhibitor properties. These proprieties could be improved through the synthesis of a bioisoster (5), where the prenyl group was replaced by the benzyl group.
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Synthesis and pharmacological evaluation of prenylated and benzylated pterocarpans against snake venom
Bioorganic & Medicinal Chemistry Letters, 2004Co-Authors: Alcides J. M. Da Silva, Antonio L. Coelho, Raphael A. M. Moraes, Diogo Pinheiro, Emerson Z. Arruda, Fabrício F.a. Fernandes, Alessandro B. C. Simas, Paulo R R Costa, Paulo A. MeloAbstract:Edunol (3), a pterocarpan isolated from Harpalyce brasiliana, a plant used in the northeast of Brazil against snakebites, was obtained by synthesis and showed antimyotoxic, Antiproteolytic and PLA2 inhibitor properties. These proprieties could be improved through the synthesis of a bioisoster (5), where the prenyl group was replaced by the benzyl group.
Linda Wang - One of the best experts on this subject based on the ideXlab platform.
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Sodium trimetaphosphate as a novel strategy for matrix metalloproteinase inhibition and dentin remineralization
Caries research, 2018Co-Authors: Rafael Simões Gonçalves, Polliana Mendes Candia Scaffa, M. C. Giacomini, Cristina De Mattos Pimenta Vidal, Heitor Marques Honório, Linda WangAbstract:The effect of sodium trimetaphosphate (STMP) as an Antiproteolytic and remineralizing agent on demineralized dentin was evaluated in vitro. The inhibitory potential of STMP at 0.5, 1.5, 3.5, and 5% against recombinant matrix metalloproteinases (MMPs) MMPs-2 and -9 was assessed by zymography. To investigate its remineralization potential, 40 bovine root specimens were obtained and subjected to a demineralization protocol to produce caries-like dentin lesions. After that, dentin surfaces were divided into 3 areas: (1) mineralized (no treatment); (2) demineralized; and (3) demineralized/treated with STMP and submitted to a pH-cycling associated or not with STMP (1.5, 3.5, or 5% STMP, 10 min of treatment). After that, superficial hardness (SH) and cross-sectional hardness (CSH) were determined. Polarized light microscopy (PLM) was used to qualitatively evaluate mineralization within the caries-like lesions. The zymographic analysis showed that STMP solution is a potent inhibitor of the gelatinolytic activity of MMPs-2 and -9 depending on the dose, since the lowest concentration (0.5%) partially inhibited the enzyme activity, while the higher concentrations completely inhibited enzyme activity. Regarding remineralization effect, only 1.5% STMP solution enhanced both the SH and CSH. PLM showed that the area treated with 1.5% STMP presented similar birefringence as mineralized sound dentin. In conclusion, 1.5% STMP solution is effective as an Antiproteolytic agent against MMPs and promotes dentin remineralization.
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Use of sodium trimetaphosphate in the inhibition of dentin matrix metalloproteinases and as a remineralizing agent.
Journal of dentistry, 2017Co-Authors: Rafael Simões Gonçalves, Polliana Mendes Candia Scaffa, M. C. Giacomini, Heitor Marques Honório, Marília Afonso Rabelo Buzalaf, Linda WangAbstract:Abstract Objectives Because of its ability to act as an Antiproteolytic agent, the effect of sodium trimetaphosphate (STMP) against specific enzymes extracted from sound dentin and its performance under acidic challenge on demineralized dentin were investigated. Methods The Antiproteolytic potential of STMP (0.5%, 1.0%, and 1.5%) was assessed in triplicate by zymography. For the evaluation of remineralization activity, 50 bovine-root dentin specimens were selected and randomly divided into 5 groups (n = 10). Three areas were determined for each specimen: 1) control (no treatment); 2) demineralized (artificial caries-like challenge); 3) treated (demineralized and subjected to pH-cycling for 7 days, and treated for 10 min with 1.5% STMP, 1.5% STMP + calcium hydroxide (Ca[OH]2), 1.5% STMP + sodium fluoride (NaF), NaF, or deionized H2O). The dentin specimens were analyzed for superficial hardness (SH) and cross-sectional hardness (CSH) at different depths (10, 30, 50, 70, 90, 110, and 220 μm) using a Knoop penetrator (10 g/10 s). Statistical analyses were performed with analysis of variance (ANOVA) and Tukey tests (p Results The zymographic analysis showed that 1.5% STMP promoted complete inhibition of gelatinolytic activity. Therefore, 1.5% STMP was investigated in association with supplemented calcium or fluoride; a combination of 1.5% STMP and Ca(OH)2 significantly increased the mechanical properties of the treated dentin. Conclusion 1.5% STMP serves as an Antiproteolytic agent against matrix metalloproteinases extracted from human dentin. Furthermore, when supplemented with Ca(OH)2, 1.5% STMP may potentially induce remineralization. Clinical significance STMP can be introduced as a novel strategy that combines enzymatic inhibition and remineralizing potential, which can serve to strengthen dentin and improve stability. STMP may have potential in the treatment of demineralized dentin lesions, especially when supplemented with calcium.
Munishwar N. Gupta - One of the best experts on this subject based on the ideXlab platform.
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An insoluble aggregate of commercially available bovine serum albumin shows Antiproteolytic activity.
Iubmb Life, 1994Co-Authors: R. John, Renu Tyagi, Munishwar N. GuptaAbstract:Chemical aggregation of bovine serum albumin by extensive chemical crosslinking with glutaraldehyde yielded an insoluble protein preparation with significant Antiproteolytic activity. This was presumably due to the presence of alpha 2-macroglobulin in bovine serum albumin preparations. Chemical crosslinking of bovine serum albumin under optimum conditions was found to increase its antitryptic activity by about four times. The results indicate that enhanced rigidity of alpha 2-macroglobulin structure increases its antitryptic activity.
Stanislaw Sulkowski - One of the best experts on this subject based on the ideXlab platform.
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Proteolytic-Antiproteolytic balance and its regulation in carcinogenesis
World journal of gastroenterology, 2005Co-Authors: Elżbieta Skrzydlewska, Mariola Sulkowska, Mariusz Koda, Stanislaw SulkowskiAbstract:Cancer development is essentially a tissue remodeling process in which normal tissue is substituted with cancer tissue. A crucial role in this process is attributed to proteolytic degradation of the extracellular matrix (ECM). Degradation of ECM is initiated by proteases, secreted by different cell types, participating in tumor cell invasion and increased expression or activity of every known class of proteases (metallo-, serine-, aspartyl-, and cysteine) has been linked to malignancy and invasion of tumor cells. Proteolytic enzymes can act directly by degrading ECM or indirectly by activating other proteases, which then degrade the ECM. They act in a determined order, resulting from the order of their activation. When proteases exert their action on other proteases, the end result is a cascade leading to proteolysis. Presumable order of events in this complicated cascade is that aspartyl protease (cathepsin D) activates cysteine proteases (e.g. cathepsin B) that can activate pro-uPA. Then active uPA can convert plasminogen into plasmin. Cathepsin B as well as plasmin are capable of degrading several components of tumor stroma and may activate zymogens of matrix metalloproteinases, the main family of ECM degrading proteases. The activities of these proteases are regulated by a complex array of activators, inhibitors and cellular receptors. In physiological conditions the balance exists between proteases and their inhibitors. Proteolytic-Antiproteolytic balance may be of major significance in the cancer development. One of the reasons for such a situation is enhanced generation of free radicals observed in many pathological states. Free radicals react with main cellular components like proteins and lipids and in this way modify proteolytic-Antiproteolytic balance and enable penetration damaging cellular membrane. All these lead to enhancement of proteolysis and destruction of ECM proteins and in consequence to invasion and metastasis.