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1.
Int Endod J ; 52(4): 424-438, 2019 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-30244498

RESUMO

AIM: To evaluate the potential biostimulatory effects of grape seed extract (GSE) on a primary culture of human pulp cells. METHODOLOGY: Human molars were used to obtain the primary pulp cell culture and 0.5-mm dentine discs. For GSE direct exposure, dose-response (0.0065-6.5%) and time response (1-60 min of contact) were examined. For transdentinal exposure, 0.65% of GSE was tested for 24 h. Cellular metabolism, nitric oxide and collagen production, and cell morphology alterations were assessed at periods of 24 and 72 h. After cell differentiation and direct exposure to GSE, the total protein production (TP), alkaline phosphatase activity (ALP) and formation of mineralization nodules (MN) were assessed. The results were analysed by parametric tests or non-parametric tests (α = 0.05). RESULTS: The lower concentration of GSE tested (0.0065%) was associated with an increase in cellular metabolism, a reduction in the production of nitric oxide and an increase in extracellular matrix synthesis (collagen). Distinct behaviours were observed for the different concentrations, without a reduction of cellular metabolism >10% compared with the control, either when applied directly or transdentinally. SEM revealed no significant change in cell morphology, except for the positive control (H2 O2 ). There was no difference in TP, ALP or MN between the control group and the group exposed to GSE. CONCLUSIONS: Treatment with grape seed extract, even at the highest concentration and longest period, caused neither direct nor transdentinal cytotoxic effects on human pulp cells. Grape seed extract components may play a biostimulatory role and protect dental pulp cells when in direct contact.


Assuntos
Extrato de Sementes de Uva , Proantocianidinas , Diferenciação Celular , Polpa Dentária , Dentina , Humanos
3.
Lett Appl Microbiol ; 67(4): 337-342, 2018 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-30027573

RESUMO

This study aims at identifying the populations of filamentous fungi present on a Brazilian contemporary painting, whose conservation status was compromised and showed evident signs of deterioration by microbial action. In addition, to correlate the biodeterioration potential of the isolated fungal strains, cellulolytic activity testing was performed and, finally, the biocide treatment against microbial growth was carried out. A total of nine isolates of filamentous fungi were detected and three distinct taxa were identified: Aspergillus flavus, Aspergillus niger and Penicillium citrinum. The detection of the enzymatic activity of the isolates by cellulolytic plate assay revealed the potential of filamentous fungal species in causing the deterioration of paintings. Our results showed that the presence of each strain of filamentous fungi correlated with the distribution of the paint colour, suggesting a tropism of certain species for specific dyes used. In addition, strains of A. niger showed a lower enzymatic activity index, despite the aesthetic damage that this fungal specie caused on the artwork. In conclusion, this study demonstrated that the identification of the microbiota obtained from the painting may help contrasting its biodeterioration and it described a successful antifungal treatment on a contemporary art piece. Contemporary art in Brazil arose from postmodernism, through the artistic manifestations included in the Neoconcrete Manifest of 1959, as well as with the use of innovative techniques. It was a consequence of the interaction between concept and language, displayed by the artists on a set of unconventional materials and objects. Despite being a 20th century painting, the concern of the artist to keep the art object in a good conservation state has driven the realization of this work and these microbial prospecting studies, associated with artwork deterioration, may contribute to the preservation of the Brazilian contemporary heritage.


Assuntos
Aspergillus flavus/isolamento & purificação , Aspergillus niger/isolamento & purificação , Corantes , Fungos/isolamento & purificação , Pinturas , Penicillium/isolamento & purificação , Antifúngicos , Aspergillus flavus/crescimento & desenvolvimento , Aspergillus niger/crescimento & desenvolvimento , Bioprospecção , Brasil , Microbiota , Penicillium/crescimento & desenvolvimento
4.
Lett Appl Microbiol ; 65(5): 431-438, 2017 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-28833313

RESUMO

This study aimed to evaluate the action of organic acids produced by the fungal population associated with the biodeterioration process of the Twelve Prophets of Aleijadinho, a set of soapstone sculptures in Congonhas, state of Minas Gerais, Brazil. For this, samples of fungi were obtained from the surface of each of the 12 outdoor stone sculptures that comprise the set of Prophets. The identification of the colonizing filamentous fungi was performed by classical microbiology and molecular methods. Some species of filamentous fungi-dependent cultivation were detected, and the presence of species Aspergillus versicolor, Curvularia lunata, Epicoccum nigrum, Penicillium citrinum and Pseudocercospora norchiensis indicated a connection with the excretion of organic acids. The acids produced by each of these fungal species were analysed quantitatively by chromatographic methods, revealing potential biodeterioration by the action of acidic metabolites excreted in the stone. SIGNIFICANCE AND IMPACT OF THE STUDY: Minas Gerais, Brazil, is vulnerable to the activities of mineral extraction industries, posing an imminent risk to United Nations Educational, Scientific and Cultural Organization (UNESCO) recognized cities, e.g. Congonhas. Many of these municipalities hold many soapstone religious sculptures and historical monuments. Consequently, soapstone is susceptible to filamentous fungi attack causing irreversible biodeterioration. Despite the concern related to nondestructive sampling of 18th century sculptures, in this study, we have discussed the factors that lead to biodeterioration of soapstone due to organic acid excretion by the fungi that damage the stone, thereby providing an insight in conserving and preserving the soapstone monuments.


Assuntos
Fungos/isolamento & purificação , Fungos/metabolismo , Sedimentos Geológicos/microbiologia , Brasil , Ecossistema , Meio Ambiente , Fungos/classificação , Fungos/genética , Sedimentos Geológicos/química , História Antiga , Escultura/história
5.
Phys Chem Chem Phys ; 19(2): 1335-1341, 2017 Jan 04.
Artigo em Inglês | MEDLINE | ID: mdl-27973632

RESUMO

This study provides a comprehensive insight into the effects of controlled off-stoichiometry on the structural and multiferroic properties of the hexagonal manganite LuMn1-xO3+δ (x = 0.02; δ ∼ 0), supported by neutron powder diffraction measurements confirming single phase P63cm symmetry and evidencing a relevant ferromagnetic component, below TN ∼ 90 K, which breaks the archetypal geometrically frustrated antiferromagnetic state typically ascribed to LuMnO3. The perturbations in the triangular disposition of spins prompt an additional electric polarization contribution and a clear enhancement of the magnetoelectric coupling which are in good agreement with the results of first principles calculations. In addition, Raman spectroscopy, dielectric permittivity, pyroelectric current and magnetic measurements as a function of temperature point out the precursor effects of the magnetic phase transitions involving a strong coupling between spins, lattice and electric order, even above the Néel temperature.

6.
Int J Sports Med ; 37(5): 369-73, 2016 May.
Artigo em Inglês | MEDLINE | ID: mdl-26855432

RESUMO

This study aimed to compare the immediate effects of 3 running technique modifications on the ankle, knee, hip and trunk kinematics and on the perceived comfort in healthy runners. The modifications were: forefoot striking pattern (FFOOT); increasing 10% of step rate (10% SR); and increasing forward trunk lean (FTL). 31 healthy runners participated. 3-dimensional lower limb and trunk kinematics were quantified while performing each condition on a treadmill. At initial contact, the FFOOT showed an increase in plantar flexion and knee external rotation, and reduction in knee flexion and adduction. During the stance phase, this condition showed greater peak knee external rotation and less mean and peak dorsiflexion and knee flexion. The 10% SR resulted in less hip flexion at initial contact. During the stance phase this technique showed less mean and peak knee flexion, peak reduction for dorsiflexion, knee abduction, hip flexion and hip adduction. At initial contact and during the stance phase, the FTL caused greater knee adduction and hip flexion. The usual running was the most comfortable technique. The techniques showed different lower limb kinematic modifications; which could potentially reduce knee injury risk. This knowledge is clinically relevant as it can be used to better prescribe techniques in prevention and rehabilitation programs.


Assuntos
, Marcha , Corrida/fisiologia , Adulto , Articulação do Tornozelo , Fenômenos Biomecânicos , Feminino , Articulação do Quadril , Humanos , Articulação do Joelho , Masculino , Rotação , Tronco , Adulto Jovem
7.
J Ethnopharmacol ; 97(2): 199-206, 2005 Feb 28.
Artigo em Inglês | MEDLINE | ID: mdl-15707752

RESUMO

In a search for natural products that could be used to control the vectors of tropical diseases, 23 extracts of medicinal plants from the northeast of Brazil have been tested for molluscicidal activity against egg masses and adults of the snail Biomphalaria glabrata, for larvicidal activity against the larvae of the mosquito Aedes aegypti, and for general toxicity against the larvae of the brine shrimp Artemia salina. Of these extracts, two were active against the adult snail, one against snail egg masses, eight against the larvae of the mosquito, and 16 showed toxicity towards the brine shrimp. Chemical tests indicated that a wide variety of natural product classes were present in those extracts that showed significant activities in the bioassays.


Assuntos
Moluscocidas/farmacologia , Extratos Vegetais/farmacologia , Plantas Medicinais , Aedes , Animais , Artemia , Biomphalaria , Brasil , Etnofarmacologia , Larva/efeitos dos fármacos , Moluscocidas/isolamento & purificação , Moluscocidas/toxicidade , Extratos Vegetais/isolamento & purificação , Extratos Vegetais/toxicidade
8.
Phytomedicine ; 8(2): 115-20, 2001 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-11315753

RESUMO

In search for plant molluscicides for the vector control of schistosomiasis, ethanolic extracts from different parts of six species of the Annonaceae family were evaluated against adult forms and egg masses of Biomphalaria glabrata. Results from accurate experiments indicate that the majority of analyzed extracts possess properties lethal to Biomphalaria glabrata, some of them with significant LD90 values (< 20 ppm), as showed for Annona crassiflora M: [pulp and seed (LD50 = 13.21), steem (2.34), root bark (3.79)], Annona glabra L. [seed (17.02)], Annona muricata [leaf (8.75)]. Emphasis is held mainly into Annona muricata L. (leaf) and Annona squamosa Veil. (root) for presenting additional toxicity toward snail egg masses.


Assuntos
Biomphalaria/efeitos dos fármacos , Magnoliopsida/classificação , Moluscocidas/farmacologia , Extratos Vegetais/farmacologia , Plantas Medicinais/química , Animais , Biomphalaria/parasitologia , Brasil , Vetores de Doenças , Etnobotânica , Humanos , Caules de Planta , Esquistossomose mansoni/prevenção & controle
9.
Int J Parasitol ; 30(11): 1199-202, 2000 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-11027788

RESUMO

In the search for new molluscicidal agents we tested the activity of lapachol and other 2-hydroxy-3-alkylnaphthoquinones possessing nitrogenated alkyl chains, against the snail Biomphalaria glabrata. Lapachol, isolapachol and nor-lapachol showed strong molluscicidal activity against the adult snail (LD(90)<10 ppm) and significant toxicity against snail egg masses (LD(90)<0.2 ppm). As lapachol is easily extracted, and the derivatives can be synthesised without any difficulty, large-scale synthesis and field tests can be conducted, with a view to large-scale molluscicidal programs.


Assuntos
Moluscocidas/farmacologia , Naftoquinonas/farmacologia , Caramujos/crescimento & desenvolvimento , Animais , Anti-Infecciosos/farmacologia , Bioensaio , Brasil , Naftoquinonas/química , Caramujos/efeitos dos fármacos
10.
Phytomedicine ; 6(6): 431-8, 2000 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-10715846

RESUMO

In a continuing search for new compounds for the control of the vectors of schistosomiasis, we have tested the activity of some Brazilian medicinal plants as sources of molluscicidal natural compounds, using two molluscicidal bioassays. Twenty-seven crude extracts, from twenty-six species belonging to nineteen families, were tested. Seven extracts showed significant molluscicidal activity against Biomphalaria glabrata adults with DL50 values of less than 50 ppm, and five of them were very active in the test using egg masses. The species most active against B. glabrata adults (LD50 value = 3.65 ppm) and their egg masses (LD50 value = 0.13 ppm) was Derris sp. Annona muricata [LD50 value (adult) = 11.86 ppm and LD50 value (egg) = 49.62 ppm], Jatropha elliptica (from Goiás state) [LD50 value (adult) = 24.80 ppm and LD50 value (egg) = 3.03 ppm] and Renealmia exaltata [LD50 value (adult) = 28.03 ppm and LD50 value (egg) = 21.67 ppm], were also considered promising molluscicidal plants.


Assuntos
Medicina Tradicional , Extratos Vegetais/farmacologia , Plantas Medicinais/química , Esquistossomose/prevenção & controle , Caramujos/efeitos dos fármacos , Animais , Brasil , Vetores de Doenças , Caramujos/parasitologia
11.
Phytother Res ; 13(8): 660-4, 1999 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-10594934

RESUMO

In the search for new molluscicidal natural products, the activity of the crude ethanol extract of the rhizome of Jatropha elliptica (Pohl.) Muell. Arg. was tested. The LC(50) was 13.07 ppm. The fractionation and purification of the extract furnished jatrophone and a mixture of jatropholones A and B, as the main compounds. They were tested against the snail Biomphalaria glabrata. Jatrophone showed an LC(50) of 1.16 ppm as a molluscicide and an LC(50) of 1.14 ppm for the assay of egg mass, while the mixture of jatropholones A and B presented an LC(50) of 58.04 ppm as a molluscicide and was not active against the second assay at a concentration up to 100 ppm.


Assuntos
Antineoplásicos Fitogênicos/farmacologia , Biomphalaria/efeitos dos fármacos , Diterpenos/farmacologia , Euphorbiaceae , Moluscocidas/farmacologia , Extratos Vegetais/farmacologia , Animais , Antineoplásicos Fitogênicos/química , Antineoplásicos Fitogênicos/isolamento & purificação , Bioensaio/métodos , Diterpenos/química , Diterpenos/isolamento & purificação , Euphorbiaceae/química , Feminino , Dose Letal Mediana , Masculino , Oviposição/efeitos dos fármacos , Oviposição/fisiologia , Extratos Vegetais/isolamento & purificação
12.
J Appl Microbiol ; 84(1): 68-71, 1998 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-15244059

RESUMO

The production and testing of a probiotic formulated with a strain of Bacillus cereus (Probiotic CenBiot) is reported. The strain was grown in fed batch fermenters, desiccated, and mixed with cornflour. To test the effect of the probiotic in controlling piglet diarrhoea, two groups of sows and their respective litters received feed supplemented with probiotic CenBiot or Furazolidone; the control group received the same basic feed but not supplemented. Probiotic CenBiot was as effective as Furazolidone, reducing the prevalence of diarrhoea to half that in the control group. It also significantly improved feed conversion, daily weight gain and total weight gain in pigs in the nursery phase. Feed conversion ratios of weaned pigs were 1.904, 2.146 and 2.099 for the groups that received Probiotic CenBiot, a commercial probiotic, and basic feed, respectively. In terms of food consumption, the Probiotic CenBiot group consumed 12.6% less than the commercial probiotic group, and 10% less than the control group, to achieve the same weight.


Assuntos
Fenômenos Fisiológicos da Nutrição Animal , Bacillus cereus , Diarreia/terapia , Probióticos , Doenças dos Suínos/terapia , Ração Animal , Animais , Anti-Infecciosos/uso terapêutico , Diarreia/metabolismo , Diarreia/veterinária , Feminino , Furazolidona/uso terapêutico , Distribuição Aleatória , Doenças dos Suínos/metabolismo , Doenças dos Suínos/fisiopatologia , Desmame , Aumento de Peso
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