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111.
Jesus LM Abreu PR Almeida MC Brito LC Soares SF de Souza DE Bernardo LC Fonseca AS Bernardo-Filho M 《Acta biologica Hungarica》2006,57(2):191-200
Since ancient times propolis has been employed for many human purposes because to their favourable properties. Blood constituents labeled with technetium-99m (99mTc) have been used in nuclear medicine procedures. Some authors have reported that synthetic or natural drugs can interfere with the labeling of blood constituents with 99mTc. The aim of this work was to evaluate the action of a propolis extract on the labeling of blood elements with 99mTc. Samples of whole blood of male Wistar rats were incubated in sequence with an aqueous propolis extract at different concentrations, stannous chloride and 99mTc, as sodium pertechnetate. Blood samples were centrifuged to separate plasma and blood cells, soluble and insoluble fractions of plasma and blood cells were also separated after precipitation in trichloroacetic acid solution and centrifugation. The radioactivity was counted and the percentage of incorporated radioactivity (%ATI) for each fraction was calculated. The data obtained showed that the aqueous propolis extract used decreased significantly the %ATI in plasma proteins at higher concentration studied. Results suggest that at high concentration the constituents of this extract could alter the labeling of plasma proteins competing with same binding sites of the 99mTc on the plasma proteins or acting as antioxidant compounds. 相似文献
112.
Pierre Neuvial Philippe Hupé Isabel Brito Stéphane Liva élodie Manié Caroline Brennetot Fran?ois Radvanyi Alain Aurias Emmanuel Barillot 《BMC bioinformatics》2006,7(1):264
Background
Array-based comparative genomic hybridization (array-CGH) is a recently developed technique for analyzing changes in DNA copy number. As in all microarray analyses, normalization is required to correct for experimental artifacts while preserving the true biological signal. We investigated various sources of systematic variation in array-CGH data and identified two distinct types of spatial effect of no biological relevance as the predominant experimental artifacts: continuous spatial gradients and local spatial bias. Local spatial bias affects a large proportion of arrays, and has not previously been considered in array-CGH experiments. 相似文献113.
The blood–brain barrier (BBB) is a highly specialized system that controls the exchanges between the blood and the central
nervous system (CNS). This barrier shields the CNS from toxic substances in the blood and provides nutrients to CNS, thus
playing an essential role in the maintenance of homeostasis. The anatomical basis of the BBB is formed by the endothelial
cells of brain microvasculature, with elaborated tight and adherens junctions, which together with pericytes, the basement
membrane, and astrocytes, as well as neurons, microglia and oligodendrocytes form the neurovascular unit. The interaction
between all these components guarantees a proper environment for neural function and a restricted permeability and transport.
Pericytes were initially reported by Rouget in 1873 and since then they have been recognized as an important component of
the BBB, despite the difficulty of their identification. Diverse functions have been assigned to pericytes, including a role
in BBB properties, hemostasis, and angiogenesis, as well as a contractile, immune, and phagocytic function. These cells are
also seen like multipotent cells and so with a great potential for therapy. Here, we review the neurovascular unit composition
and the interplay between the diverse components, addressing pericytes with a particular detail. 相似文献
114.
Gondim DV Costa JL Rocha SS Brito GA Ribeiro Rde A Vale ML 《Canadian journal of physiology and pharmacology》2012,90(4):395-405
This study investigated the antinociceptive and anti-inflammatory effects of electroacupuncture (EA) on zymosan-induced acute arthritis of the rat temporomandibular joint (TMJ). Male Wistar rats were injected with saline or zymosan (control group; 2?mg) into the left TMJ. Low frequency EA (10?Hz, 30?min) was performed at acupoints (LI4, LI11, ST36, ST44) or sham points 2?h after or 1?h before zymosan administration. Mechanical hypernociception was accessed by the electronic Von Frey method after zymosan administration. Rats were sacrificed 6?h after zymosan administration and the joint was removed for histopathological analysis, myeloperoxidase activity assessment, vascular permeability observations, and immunohistochemical verification of inflammatory mediators. The results showed that EA inhibited zymosan-induced hypernociception, compared with the control group and with the sham group (p?< 0.05). The results showed that EA inhibited inflammatory parameters such as neutrophil migration, vascular permeability, and tumour necrosis factor α (TNF-α), cyclooxygenase-2 (COX-2), and inducible nitric oxide synthase (iNOS) expression in the TMJ compared with the sham group (p < 0.05). Histopathological analysis showed that EA significantly inhibited edema and periarticular infiltration (p?< 0.05) compared with the control and sham groups. EA at acupoints produced antinociceptive and anti-inflammatory effects on zymosan-induced arthritis in the rat TMJ. 相似文献
115.
Diego Gaitán Manuel Olivares Bo L?nnerdal Alex Brito Fernando Pizarro 《Biological trace element research》2012,150(1-3):68-73
The absorption of heme iron has been described as distinctly different from that of non-heme iron. Moreover, whether heme and non-heme iron compete for absorption has not been well established. Our objective was to investigate the potential competition between heme and non-heme iron as ferrous sulfate for absorption, when both iron forms are ingested on an empty stomach. Twenty-six healthy nonpregnant women were selected to participate in two iron absorption studies using iron radioactive tracers. We obtained the dose?Cresponse curve for absorption of 0.5, 10, 20, and 50?mg heme iron doses, as concentrated red blood cells. Then, we evaluated the absorption of the same doses, but additionally we added non-heme iron, as ferrous sulfate, at constant heme/non-heme iron molar ratio (1:1). Finally, we compare the two curves by a two-way ANOVA. Iron sources were administered on an empty stomach. One factor analysis showed that heme iron absorption was diminished just by increasing total heme iron (P?<?0.0001). The addition of non-heme iron as ferrous sulfate did not have any effect on heme iron absorption (P?=?NS). We reported evidence that heme and non-heme iron as ferrous sulfate does not compete for absorption. The mechanism behind the absorption of these iron sources is not clear. 相似文献
116.
do Prado MF Coelho AC de Brito JP Ferreira DO Junior AW Menecucci Cda S de Queiroz AB Garcia LB Cardoso CL Tognim MC 《Letters in applied microbiology》2012,54(6):564-567
Aims: The objective of this study was to assess the antimicrobial efficacy of alcohol‐based hand gels according to European Norm 1500 (EN 1500). Methods and Results: We assessed the antimicrobial efficacy of 12 alcohol‐based hand gels produced in Brazil, containing 70% w/w or v/v ethyl alcohol as the active ingredient, according to EN 1500, with a 30‐s application. In addition, 70% w/w ethyl alcohol and three alcohol‐based hand rubs commonly used in Europe and effective according to EN 1500 were also tested. Eight of 12 (67%) alcohol‐based hand gels produced in Brazil failed by EN 1500. In contrast, 70% w/w ethyl alcohol and European alcohol‐based hand rubs were approved by EN 1500. Conclusions: In this study, the majority of Brazilian alcohol‐based hand gels showed limited efficacy on hand hygiene within 30 s. Significance and Impact of the Study: The findings of this study may be used as an important argument to motivate Brazilian manufacturers to improve the antimicrobial efficacy of alcohol‐based hand gels, because it is prudent to suppose that alcohol‐based hand gels can be recommended for use in healthcare settings only if they show antimicrobial activity at least similar to that of alcohol‐based liquid preparations, including the traditional 70% w/w ethyl alcohol. 相似文献
117.
Effects of compounds from Passiflora edulis Sims f. flavicarpa juice on blood coagulation and on proteolytic enzymes 总被引:1,自引:0,他引:1
Sato AC Andrade SA Brito MV Miranda A Sampaio MU de Abreu Maffei FH Oliva ML 《Protein and peptide letters》2012,19(5):501-508
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. flavicarpa extract. After purification process, two compounds of distinct molecular weight and inhibitory action were better characterized. One is a trypsin inhibitor similar to inhibitors from Bowman-Birk family, named PeTI-I12, and other is a compound active in coagulation that prolongs aPTT and PT, but does not change TT. The aim of this study is to provide evidence that passion fruit extract's components play a role on hemostasis and therefore may be relevant in the handling of patients treated with anticoagulants or suffering hemorrhagic diseases. 相似文献
118.
de Brito AF Martins JL Fajemiroye JO Galdino PM De Lima TC Menegatti R Costa EA 《Life sciences》2012,90(23-24):910-916
AimsOur study focuses on the design and synthesis of a new piperazinic derivate, 4-(1-phenyl-1h-Pyrazol-4-Ylmethyl)-Piperazine-1-Carboxylic Acid Ethyl ester (LQFM008), and evaluation of its anxiolytic-like profile in Swiss mice.Main methodsLQFM008 was evaluated in a screening test of the central nervous system including the rota-rod, sodium pentobarbital-induced sleep, open field, elevated plus maze and light–dark box tests.Key findingsLQFM008 induced convulsions at the dose of 1.1 mmol/kg (i.p., s.c. or p.o.). LQFM008 up to 400 μmol/kg had no effect in the rota rod test. In the open field test, LQFM008 increased the number of crossings and the time spent at the central area as well as the sleeping time in sodium pentobarbital-induced sleep. In the elevated plus maze and light–dark box tests, this compound showed an anxiolytic-like activity. This anxiolytic-like activity was antagonized by NAN-190 (5-HT1A antagonist) but not by flumazenil (benzodiazepine antagonist).SignificanceThe compound LQFM008 showed anxiolytic-like activity which may involve serotonergic pathway. 相似文献
119.
Rebelo H Froufe E Brito JC Russo D Cistrone L Ferrand N Jones G 《Molecular ecology》2012,21(11):2761-2774
The barbastelle (Barbastella barbastellus) is a rare forest bat with a wide distribution in Europe. Here, we combine results from the analysis of two mtDNA fragments with species distribution modelling to determine glacial refugia and postglacial colonization routes. We also investigated whether niche conservatism occurs in this species. Glacial refugia were identified in the three southern European peninsulas: Iberia, Italy and the Balkans. These latter two refugia played a major role in the postglacial colonization process, with their populations expanding to England and central Europe, respectively. Palaeo‐distribution models predicted that suitable climatic conditions existed in the inferred refugia during the last glacial maximum (LGM). Nevertheless, the overlap between the current and the LGM distributions was almost inexistent in Italy and in the Balkans, meaning that B. barbastellus populations were forced to shift range between glacial and interglacial periods, a process that probably caused some local extinctions. In contrast, Iberian populations showed a ‘refugia within refugium’ pattern, with two unconnected areas containing stable populations (populations that subsisted during both glacial and interglacial phases). Moreover, the match between LGM models and the refugial areas determined by molecular analysis supported the hypothesis of niche conservatism in B. barbastellus. We argue that geographic patterns of genetic structuring, altogether with the modelling results, indicate the existence of four management units for conservation: Morocco, Iberia, Italy and UK, and Balkans and central Europe. In addition, all countries sampled possessed unique gene pools, thus stressing the need for the conservation of local populations. 相似文献
120.
Mercedes M. C. Bustamante Darlan Q. de Brito Alessandra R. Kozovits Gustavo Luedemann Thiago R. B. de Mello Alexandre de Siqueira Pinto Cássia B. R. Munhoz Frederico S. C. Takahashi 《Plant Ecology》2012,213(5):795-808
The Brazilian Cerrado is a diversity hotspot due to its high level of endemism and rapid loss of habitats. It is estimated
that the number of herbaceous species is four times higher than that of woody species. Increasing levels of nitrogen additions
to natural ecosystems have been indicated as a determinant of biodiversity loss. We investigated the effects of nutrient additions
on the productivity (aboveground and belowground) and on diversity of the herbaceous-subshrub layer of a Brazilian savanna
(cerrado stricto sensu). The experiment was carried out in the IBGE Ecological Reserve, near Brasília, Brazil. Between 1998
and 2006, N, P, N plus P, or Ca were applied to sixteen 225 m2 plots, arranged in a completely randomized design. Aboveground biomass was compared 1 year after the first fertilization
and 10 years later. Floristic diversity was significantly different (P < 0.01) between the treatments. The highest and lowest species richness were presented in control and NP, respectively. The
addition of P alone or in combination with N induced invasion by Melinis minutiflora (exotic C4 grass). The aboveground biomass of this species was higher in NP and P plots. In the N treatment, Echinolaena inflexa (native C3 grass) presented elevated cover and biomass but M. minutiflora was absent. The invasion by alien species resulted in negative impacts on native grass species. Besides changes in aboveground
biomass, addition of N and P also led, although to a lesser extent, to changes in the root morphology and biomass, but these
responses were modulated by seasonal variation in soil moisture. The results suggest that environmental changes in nutrient
availability can lead to important consequences for diversity and functioning of this savanna where the numerous rare species
have more chance to persist under dystrophic conditions as some species that tend to be dominant would be less competitive. 相似文献