Validation of an alternative analytical method for the quantification of antioxidant activity in plant extracts

Coordenação de Aperfeiçoamento de Pessoal de Nível Superior (CAPES)

Extracts from a note communicated by the French Government to the Secretary-General of the United Nations

Note about training course which could be organized in France for technicians from the under-developed countries holding United Nations felleowships

Healing of fresh frozen bone allograft with or without platelet-rich plasma: A histologic and histometric study in rats

Purpose: This study histomorphometrically analyzed the effect of autogenous platelet-rich plasma (PRP) on healing of fresh frozen bone allograft (FFBA) in bony defects in rat calvaria. Materials and Methods: A 5mm-diameter defect was created in the calvarium of 30 rats. Animals were divided into three groups: C (defect was filled by blood clot only), FFBA (defect was filled with 0.01mL of FFBA), and FFBA/PRP (defect was filled with 0.01mL of FFBA combined with 100μL of PRP). All animals were euthanized at 30 days postoperatively. Histomorphometry and histology analyses were performed. Data were statistically analyzed (analysis of variance, Tukey, p<.05). Results: FFBA had a statistically smaller new bone area than groups FFBA/PRP and C. No statistically significant differences were observed between groups FFBA and FFBA/PRP with regard to remaining bone graft particle area. Conclusion: It can be concluded that (1) PRP improved the incorporation of FFBA, increasing the amount of new bone formed; (2) PRP has not influenced the resorption of nonviable particles of the FFBA; and (3) presence of remaining FFBA particles might have accounted for the smaller amount of new bone observed in group FFBA when compared with control group. © 2011 Wiley Periodicals, Inc.

The economic development of Bolivia: summary and extracts

Includes bibliography

In vitro activity of pineapple extracts (Ananas comosus, Bromeliaceae) on Rhipicephalus (Boophilus) microplus (Acari: Ixodidae)

Measures to control the cattle tick, Rhipicephalus (Boophilus) microplus, based only on chemical products are becoming unsustainable, mainly because of the development of resistance. The objective of this study was to test the effect of the aqueous extract of pineapple skin (AEPS) and bromelain extracted from the stem (Sigma-Aldrich®, B4882) on engorged females and larvae of R. (B.) microplus in vitro. These substances were diluted in water and evaluated at eight concentrations. Engorged females were collected and distributed in groups of 10, with three repetitions for each treatment. After immersion in the solutions, the females were placed in an incubator for observation of survival, oviposition and larval hatching. The larval packet method was used, also with three repetitions with about 100 larvae each. The packets were incubated and the readings were performed after 24h. The estimated reproduction and efficacy of the solutions were calculated. The LC50 and LC90 were estimated using the Probit procedure of the SAS program. The eight concentrations were compared within each treatment by the Tukey test. For the experiment with engorged females, the most effective concentrations were 125, 250 and 500mg/mL: 33%, 48% and 59% for the AEPS and 27%, 51% and 55% for the bromelain. The LC50 and LC90 values were, respectively, 276 and 8691mg/mL for AEPS and 373 and 5172mg/mL for bromelain. None of the dilutions tested was effective against the larvae of R. (B.) microplus. This is the first report of the action of pineapple extracts or their constituents on cattle ticks. The results demonstrate that further studies regarding composition of tick cuticle, with evaluation of other solvents and formulations, should be conducted seeking to enhance the effect of pineapple extracts and compounds against this ectoparasite. © 2013 Elsevier Inc.

Phytotoxicity of organic extracts of Turnera ulmifolia L. and Turnera diffusa Willd. ex Schult. in cucumber seeds

We evaluated the phytotoxic effects that the hexane, ethyl acetate and methanol extracts from leaves and branches of the species Turnera ulmifolia L. and Turnera diffusa Willd. ex Schult. (Turneraceae), at concentrations of 1.25, 2.50, 3.75 and 5.00 mg ml-1, have on seed germination and seedling development in cucumber (Cucumis sativus L.). None of the extracts tested prevented germination, although the ethyl acetate extracts of T. diffusa, at 3.75 and 5.00 mg ml-1, reduced the mean germination speed and time to germination. Hexane extracts of both species reduced the main root length, number of secondary roots and hypocotyl length. In the ethyl acetate and methanol extracts, the number of secondary roots and hypocotyl length varied by species and concentration. Ethyl acetate extracts of T. ulmifolia at ≤ 2.50 mg ml-1stimulated growth of the main root and hypocotyl, as did T. ulmifolia methanol extracts at 1.25 and 3.75 mg ml-1; all other extract/concentration combinations had an inhibitory effect on those parameters. The hexane and ethyl acetate extracts of T. diffusa inhibited the formation of secondary roots and of the main root, although significant inhibition of hypocotyl growth was observed only at ≥ 2.50 mg ml-1. Comparatively, T. diffusa extracts inhibited development to a greater degree, thus presenting greater allelopathic potential, than did T. ulmifolia extracts.

Antioxidant activity of basil and oregano extracts added to soybean oil for accelerated storage test

The objective of this research was to evaluate the antioxidant activity of extract of basil and oregano, and its synergistic effect when added to soybean oil and subjected to accelerated storage test. Extracts of basil, oregano and mixtures of both were applied to soybean oil at a concentration of 2.000mg/kg, then the extracts were heated in an oven at 60C for a period of 10 days. Samples were taken every 2 days and analyzed for concentrations of peroxides and conjugated dienes. Synthetic antioxidant tert-butylhydroquinone (TBHQ) at a concentration of 50mg/kg and soybean oil free antioxidant (control) subject to the same conditions were used as benchmarks. The results showed that the antioxidant effect decreases according to oil heating for all treatments. However, the synthetic antioxidant showed superior protection to the soybean oil during the formation of primary oxidation compounds, followed by the natural extracts, which showed no synergism. © 2012 Wiley Periodicals, Inc.

Influence of current density on crystalline structure and magnetic properties of electrodeposited Co-rich CoNiW alloys

The influence of current density, at the interval 5-100 mA cm-2, on the structural and magnetic properties of electrodeposited (Co 100-xNix)100-yWy alloys (x = 23-33.5 at. % Ni, y = 1.7-7.3 at. % W) was studied from a glycine-containing bath. W-content decreases with the increase of the current density magnitude. X-ray data have shown stabilization of hexagonal close packed, face centered cubic or a mixture of these structures by modulating the applied cathodic current density, for values lower than 50 mA cm-2. Two structural phase transitions were observed: one from hexagonal close packed to face centered cubic structural transition occurring for a current density of 20 mA cm -2, and another one, from cubic crystalline phase to amorphous state, which happens for values higher than 50 mA cm-2. These structural phase transitions seem to be associated with the W-content as well as average crystalline grain sizes that reduce with increasing the current density value. The grain size effect may explain the face centered cubic stabilization in Co-rich CoNiW alloys, which was initially assumed to be basically due to H-adsorption/incorporation. Magnetic properties of Co-rich CoNiW alloys are strongly modified by the current density value; as a result of the changes on the W-content and their structural properties© 2013 Elsevier B.V. All rights reserved.

Cytotoxicity of Brazilian plant extracts against oral microorganisms of interest to dentistry

Background: With the emergence of strains resistant to conventional antibiotics, it is important to carry studies using alternative methods to control these microorganisms causing important infections, such as the use of products of plant origin that has demonstrated effective antimicrobial activity besides biocompatibility. Therefore, this study aimed to evaluate the antimicrobial activity of plant extracts of Equisetum arvense L., Glycyrrhiza glabra L., Punica granatum L. and Stryphnodendron barbatimam Mart. against Staphylococcus aureus, Staphylococcus epidermidis, Streptococcus mutans, Candida albicans, Candida tropicalis, and Candida glabrata, and to analyze the cytotoxicity of these extracts in cultured murine macrophages (RAW 264.7).Methods: Antimicrobial activity of plant extracts was evaluated by microdilution method based on Clinical and Laboratory Standards Institute (CLSI), M7-A6 and M27-A2 standards. The cytotoxicity of concentrations that eliminated the microorganisms was evaluated by MTT colorimetric method and by quantification of proinflammatory cytokines (IL-1β and TNF-α) using ELISA.Results: In determining the minimum microbicidal concentration, E. arvense L., P. granatum L., and S. barbatimam Mart. extracts at a concentration of 50 mg/mL and G. glabra L. extract at a concentration of 100 mg/mL, were effective against all microorganisms tested. Regarding cell viability, values were 48% for E. arvense L., 76% for P. granatum L, 86% for S. barbatimam Mart. and 79% for G. glabra L. at the same concentrations. About cytokine production after stimulation with the most effective concentrations of the extracts, there was a significant increase of IL-1β in macrophage cultures treated with S. barbatimam Mart. (3.98 pg/mL) and P. granatum L. (7.72 pg/mL) compared to control (2.20 pg/mL) and a significant decrease of TNF-α was observed in cultures treated with G. glabra L. (4.92 pg/mL), S. barbatimam Mart. (0.85 pg/mL), E. arvense L. (0.83 pg/mL), and P. granatum L. (0.00 pg/mL) when compared to control (41.96 pg/mL).Conclusions: All plant extracts were effective against the microorganisms tested. The G. glabra L. extract exhibited least cytotoxicity and the E. arvense L. extract was the most cytotoxic. © 2013 de Oliveira et al.; licensee BioMed Central Ltd.

Use of platelet-rich plasma in the treatment of deep corneal ulcers induced in rabbits.clinical and histomorphometric evaluation

The repair process induced corneal ulcer in rabbits using platelet-rich plasma in the form of eyedrop or clot was clinically evaluated and compared. Sixty rabbits were divided into four groups of 15 animals, denominated platelet group (PG), clot group (CLG), control group (CG), and amniotic control group (AG). Experimental groups were then subdivided into three groups (M4, M7, M30), corresponding to the end of the evaluation period. There were no differences between treatments regarding ocular sensitivity, chemosis and ocular secretion. The groups treated with PRP either as eyedrop or a clot showed less opacity than the animals treated only with amniotic membrane at the moment of the final evaluation. The presence of corneal ulcers in the groups treated with PRP showed lower intensity than the other groups. Histomorphometric examination showed that corneal epithelization in the initial phase of the lesion was greater when using PRP. The use of amniotic membrane promoted corneal epithelial and stromal thickness, as well as synergism when associated to PRP.

Development of a new method to prepare nano-/microparticles loaded with extracts of azadirachta indica, their characterization and use in controlling plutella xylostella

Biodegradable nanoparticles have been widely explored as carriers for controlled delivery of therapeutic molecules; however, studies describing the development of nanoparticles as carriers for biopesticide products are few. In this work, a new method to prepare nanoparticles loaded with neem (Azadirachta indica) extracts is presented. In this study, nanoparticles were formulated as colloidal suspension and (spray-dried) powder and characterized by evaluating pH, particle size, zeta potential, morphology, absolute recovery, and entrapment efficiency. A high-performance liquid chromatography method was used for nanoparticle characterization. The best formulations presented absolute recovery and entrapment efficiencies of approximately 100% and a release profile based on swelling and relaxation of the polymer or polymer erosion. The biological data of the formulated products against Plutella xylostella showed 100% larval mortality. The nanoparticle information improved the stability of neem products against ultraviolet radiation and increased their dispersion in the aqueous phase. © 2013 American Chemical Society.

Platelet-Rich Plasma And Chronic Wounds: Remaining Fibronectin May Influence Matrix Remodeling And Regeneration Success

Background: Platelet-rich plasma has been largely used as a therapeutic option for the treatment of chronic wounds of different etiologies. The enhanced regeneration observed after the use of platelet-rich plasma has been systematically attributed to the growth factors that are present inside platelets' granules. Aim: We hypothesize that the remaining plasma and platelet-bound fibronectin may act as a further bioactive protein in platelet-rich plasma preparations. Methods: Recent reports were analyzed and presented as direct evidences of this hypotheses. Results: Fibronectin may directly influence the extracellular matrix remodeling during wound repair. This effect is probably through matrix metalloproteinase expression, thus exerting an extra effect on chronic wound regeneration. Conclusions: Physicians should be well aware of the possible fibronectin-induced effects in their future endeavors with PRP in chronic wound treatment. © 2013 International Society for Cellular Therapy.

Duração do teste de germinação de Brachiaria brizantha cv. Marandu (Hochst. ex A. Rich ) Stapf

Conselho Nacional de Desenvolvimento Científico e Tecnológico (CNPq)

Avaliação da toxicidade e caracterização de hidrocarbonetos presentes em águas de rios que recebem efluente de indústria petroquímica

Pós-graduação em Ciências Biológicas (Biologia Celular e Molecular) - IBRC

Estudo da atividade antioxidante em frutas nativas e exóticas brasileiras

Conselho Nacional de Desenvolvimento Científico e Tecnológico (CNPq)