Publications by authors named "Maria Cristina dos Santos"

Article Synopsis
  • * The study investigated whether antibodies against Potamotrygon motoro venom could neutralize its harmful effects using protocols on mice, including seroneutralization and vaccination.
  • * Results showed that neither protocol fully neutralized the venom’s effects, but vaccination with stinger extract did prevent systemic muscle damage, and different immune responses were triggered depending on the method used.
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Ethnopharmacological Relevance: In the region of Western Pará, Amazonia, Brazil, Philodendron megalophyllum is widely used for the treatment of envenomations caused by bites from venomous snakes. The traditional use of plants is usually done through oral administration of an infusion (decoction) soon after the bite occurs. The efficiency of aqueous extracts of P.

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The study aimed to evaluate heat-treated bean residue meal (Phaseolus vulgaris)-BRM-as an alternative protein source in diets for Nile tilapia fish. A completely randomized design was used, totaling four (n = 4) dietary treatments: diet without BRM (CON), raw BRM (RBRM) and heat-treated BRM at 100 °C for 15 min (BRM15), and 30 min (BRM30) before inclusion in diets. Nile tilapia fingerlings (1.

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Viper snake (Cdr) is a subspecies found in northern area of Brazil. Among the snakes of genus subspecies, the venom of Cdr presents highest level of crotoxin, which is the major component of snake venoms, formed by two subunits (crotapotin and a phospholipase A named CBr) and presents potent neurotoxic activity. Curiously, the venom of (CdrV) is better neutralized by antibothropic than by anticrotalic serum, strongly suggesting that this venom has similarities with venom of genus snakes with regard to the ability to induce inflammation.

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Introduction: Antiphospholipid antibodies (aPL) are described in individuals with leprosy without the clinical features of antiphospholipid antibody syndrome (APS), a condition involving thromboembolic phenomena. We have described the persistence of these antibodies for over 5 years in patients with leprosy after specific treatment.

Objectives: To determine whether epidemiological, clinical and immunological factors played a role in the long-term persistence of aPL antibodies in leprosy patients after multidrug therapy (MDT) had finished.

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Fish immune systems have become the subject of several studies due to the growing development of aquaculture and fisheries, and the demand for healthy produce for human consumption. Among the parasites responsible for diseases in fish farming, helminths stand out because they cause infections in farmed fish and decrease food conversion, zootechnical performance and meat quality. In the present review, the components that participate in the innate and adaptive immune responses of teleost fish that have so far been described are presented in order to summarize the defenses that these hosts have recourse to, in combating different groups of helminth parasites.

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Purpose: To investigate whether MMP-13 g.-77 A > G (rs2252070) gene polymorphism is associated with early implants loss.

Materials And Methods: Two hundred nonsmoking volunteers in good oral health, > 18 years of age, and found to be periodontally healthy by clinical examination were matched by age, sex, and implant position and separated into two groups: control group (100 patients with one or more healthy implants for a minimum of 1 year) and test group (100 patients who had suffered early implant loss, considered when implants presented mobility and/or pain before or during abutment connection, requiring their removal).

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The electronic structure of semiconducting carbon nanotubes selected through polymer functionalization is routinely verified by measuring the spectral van Hove singularity signature under ultraclean vacuum conditions. Interpreting the effect of unperturbed polymer adsorption on the nanotube energetic bands in solvent media is experimentally challenging owing to solvent molecular crowding around the hybrid complex. Here, a liquid-based scanning tunneling microscope and spectroscope operating in a noise-free laboratory is used to resolve the polymer-semiconducting carbon-nanotube-underlying graphene heterostructure in the presence of encompassing solvent molecules.

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Ethnopharmacological Relevance: Extracts of leaves and bark of Aniba fragrans are used as tea (decoction) to treat snakebites in communities in the Brazilian Amazon. The aqueous extract of the leaves of A. fragrans has been proven to be effective against Bothrops venom, but only when pre-incubated with the venom.

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Ethnopharmacological Importance: The effectiveness of aqueous extract of Bellucia dichotoma Cogn. (Melastomataceae) specimems collected in Santarém, PA, against some biological activities of Bothrops atrox venom (BaV) has been scientifically proven. Here, we analyzed the components and assessed the anti-snakebite potential of aqueous extracts of bark of B.

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Oral manifestations of common variable immunodeficiency (CVID) are rare, have rarely been studied and have given controversial results. There are few data about IgA, IgG, and IgM antibody salivary levels in the literature, and there are few papers about the clinical impact of antibody deficiencies and CVID on the oral health of such patients. The aim of this study was to measure serum and salivary IgA, IgG, and IgM levels in CVID participants and controls, and to associate immunoglobulin levels with caries and periodontal disease.

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As a novel and efficient surface analysis technique, graphene-enhanced Raman scattering (GERS) has attracted increasing research attention in recent years. In particular, chemically doped graphene exhibits improved GERS effects when compared with pristine graphene for certain dyes, and it can be used to efficiently detect trace amounts of molecules. However, the GERS mechanism remains an open question.

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Graphene nanoribbons with well defined edges have been shown to possess high conductivities and behave like a quantum wire. Methods from synthetic organic chemistry have successfully been applied to produce such nanoribbons with smooth and chemically stable edges by saturation with hydrogen. Herein, we present ab initio calculations in a family of molecules related to the thinnest graphene nanoribbon, substitutionally doped with sulfur, for which synthetic methods are available.

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Envenomation by snakes of the species Bothrops atrox induces local and systemic effects. Local effects include drastic tissue damage and a marked inflammatory response as a result of the synthesis and release of a variety of protein and lipid mediators. Toll-like receptor (TLR) signaling pathways can play an important role in this response, leading to synthesis of these inflammatory mediators.

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Graphene-based sensors are among the most promising of graphene's applications. The ability to signal the presence of molecular species adsorbed on this atomically thin substrate has been explored from electric measurements to light scattering. Here we show that the adsorbed molecules can be used to sense graphene properties.

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Ethnopharmacological Relevance: Ethnobotanical studies have shown that Plathymenia reticulata Benth. (Fabaceae) has been widely used in cases of snake envenomation, particularly in Northern Brazil. In light of this, the aim of this study was to evaluate the inhibitory potential of the condensed-tannin-rich fraction obtained from the bark of P.

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Ethnopharmacological Relevance: The plant species Connarus favosus is used in folk medicine in the west of Pará state, Brazil, to treat snakebites.

Aim Of The Study: To investigate the potential of the aqueous extract of Connarus favosus (AECf) to inhibit hemorrhagic and phospholipase A2 activities induced by Bothrops atrox venom (BaV) and to determine the antioxidant and antimicrobial potentials of the extract.

Materials And Methods: AECf was analyzed phytochemically for phenolics (condensed tannins and hydrolyzable tannins) by colorimetry.

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The Amazon region reports the highest incidence of snakebite envenomings in Brazil. We aimed to describe the epidemiology of snakebites in the state of Amazonas and to investigate factors associated with disease severity and lethality. We used a nested case-control study, in order to identify factors associated with snakebite severity and mortality using official Brazilian reporting systems, from 2007 to 2012.

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Ethnopharmacological Relevance: The poor distribution and limited availability of antivenoms in Brazil have led to greater use of plants to treat snakebites. Very often such plants are the only alternative available to riverside communities.

Materials And Methods: Direct questionnaire-based interviews were conducted with members of the Cucurunã, São Pedro and Alter do Chão communities in Santarém, Pará, Brazil.

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Large-area Si-doped graphene (SiG) is controllably synthesized for the first time. A much-enhanced molecular-sensing performance is achieved when SiG is used as a probing surface. This will open up opportunities for developing high-performance sensors that are able to detect trace amounts of organic and fluorescent molecules.

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Bellucia dichotoma Cogn. (Melastomataceae) is one of various plant species used in folk medicine in the west of the state of Pará, Brazil, to treat snake bites. Many studies have been carried out to evaluate the effectiveness of anti-snake bite plants, but few of these use the same preparation methods and doses as those traditionally used by the local populations.

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Water has been predicted theoretically and observed experimentally to exhibit a wetting transition on graphite. Previous study of this problem was based on quite uncertain water-graphite interaction potentials. This paper computes the wetting temperature on graphite using recent, more realistic, interactions.

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Injuries caused by freshwater stingrays are characterized by intense pain and pathological changes at the lesion site, including oedema, erythema and, in most cases, necrosis. In this study, the systemic myotoxic activity induced by mucus extracts from the dorsal region and stinger of the stingrays Plesiotrygon iwamae and Potamotrygon motoro was described, analysed and quantified. Twenty-four hours after injection of 400 μg of the extracts into the gastrocnemius muscle of mice, the following effects were observed: coagulative necrosis of the muscle tissue, muscle fibre regeneration and the presence of inflammatory infiltrates, including neutrophils, macrophages, and a reduced number of eosinophils and lymphocytes.

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Background: To date, flow cytometric immunophenotyping has not been used to investigate immune patterns in saliva samples from individuals with inflammatory processes in the oral cavity, such as chronic periodontitis (CP). Saliva analysis could be a non-invasive method for evaluating oral health. The objective of this study is to determine the phenotype of leukocytes and total immunoglobulin A (IgA), IgG, and IgM titers in the saliva of individuals with CP.

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