916 resultados para peripheral venous catheters
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Temporomandibular disorders represent one of the major challenges in dentistry therapeutics. This study was undertaken to evaluate the time course of carrageenan-induced inflammation in the rat temporomandibular joint (TMJ) and to investigate the role of tachykinin NK(1) receptors. Inflammation was induced by a single intra-articular (i.art.) injection of carrageenan into the left TMJ (control group received sterile saline). Inflammatory parameters such as plasma extravasation, leukocyte influx and mechanical allodynia (measured as the head-withdrawal force threshold) and TNF alpha and IL-1 beta concentrations were measured in the TMJ lavages at selected time-points. The carrageenan-induced responses were also evaluated after treatment with the NK(1) receptor antagonist SR140333. The i.art. injection of carrageenan into the TMJ caused a time-dependent plasma extravasation associated with mechanical allodynia, and a marked neutrophil accumulation between 4 and 24 h. Treatment with SR140333 substantially inhibited the increase in plasma extravasation and leukocyte influx at 4 and 24 h, as well as the production of TNF alpha and IL-1 beta into the joint cavity, but failed to affect changes in head-withdrawal threshold. The results obtained from the present TMJ-arthritis model provide, for the first time, information regarding the time course of this experimental inflammatory process. In addition, our data show that peripheral NK(1) receptors mediate the production of both TNF alpha and IL-1 beta in the TMJ as well as some of the inflammatory signs, such as plasma extravasation and leukocyte influx, but not the nociceptive component. 2008 European Federation of Chapters of the International Association for the Study of Pain. Published by Elsevier Ltd. All rights reserved.
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Background and aims Toxoplasmic retinochoroiditis may recur months or years after the primary infection. Rupture of dormant cysts in the retina is the accepted hypothesis to explain recurrence. Here, the authors present evidence supporting the presence of Toxoplasma gondii in the peripheral blood of immunocompetent patients. Methods Direct observation by light microscopy and by immunofluorescence assay was performed, and results were confirmed by PCR amplification of parasite DNA. Results The authors studied 20 patients from Erechim, Brazil, including acute infected patients, patients with recurrent active toxoplasmic retinochoroiditis, patients with old toxoplasmic retinal scars, and patients with circulating IgG antibodies against T gondii and absence of ocular lesions. Blood samples were analysed, and T gondii was found in the blood of acutely and chronically infected patients regardless of toxoplasmic retinochoroiditis. Conclusions The results indicate that the parasite may circulate in the blood of immunocompetent individuals and that parasitaemia could be associated with the reactivation of the ocular disease.
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Introduction: TLR-4 has also been identified as a receptor for endogenous alarmins, which are increased post transplantation. TLR-4 has also been associated with a polymorphism that could impact graft outcome. Objective: To assess the expression of TLR-4 in kidney transplant patients carrying or not a polymorphism. Methods: TLR-4 polymorphism (A299G/T399I) was studied in 200 renal transplant patients. Healthy volunteers were also enrolled as control group. The polymorphism analysis was performed using restriction enzymes technique (RFLP). Functionality of TLR-4 polymorphism was assessed in samples from controls by quantification of TNF-alpha after LPS stimulus. TLR-4 and -2 expressions were also analyzed by flow cytometry. Results: TLR-4 polymorphism was present in 8.5% of renal transplant patients. This polymorphism was associated with impairment in TNF-alpha secretion. In general, in renal transplant patients, TLR-4 expression in monocytes and in neutrophils was lower than in health volunteers. TLR-2 and TLR-4 expressions in healthy volunteers with A299G/T399I TLR-4 polymorphism was higher than in wild-type genotype healthy volunteers (p<0.01 and p<0.05, respectively), and also higher than A299G/T399I TLR-4 polymorphism renal transplant patients (p<0.05). TLR-2 expression on neutrophils in wild-type genotype renal transplant patients was higher compared to wild-type genotype healthy volunteers, and was also higher in relation to A299G/T399I kidney transplanted patients (p<0.01). Conclusion: Stable renal transplant patients with TLR-4 polymorphism have a lower expression of TLR-4 and TLR-2 receptors in peripheral mononuclear cells, which ultimately indicate a less responsiveness for alarmins. (C) 2010 Elsevier B.V. All rights reserved.
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Apocynin has been extensively used as an inhibitor of NADPH oxidase (NOX) in many experimental models using phagocytic and non-phagocytic cells. Currently, there is some controversy about the efficacy of apocynin in non-phagocytic cells, but in phagocytes the reported results are consistent, which could be due to the presence of myeloperoxidase in these cells. This enzyme has been proposed as responsible for activating apocynin by generating its dimer, diapocynin, which is supposed to be the active compound that prevents NADPH oxidase complex assembly and activation. Here, we synthesized diapocynin and studied its effect on inhibition of gp91(phox) RNA expression. We found that diapocynin strongly inhibited the expression of gp91(phox)mRNA in peripheral blood mononuclear cells (PBMC). Only at a higher concentration, apocynin was able to exert the same effect. We also compared the apocynin and diapocynin efficacy as inhibitors of tumor necrosis factor-alpha (TNF-alpha) and interleukin-10 (IL-10) production in response to lipopolysaccharide (LPS)-activated PBMC. Although apocynin did inhibit TNF-alpha production, diapocynin had a much more pronounced effect, on both TNF-alpha and IL-10 production. In conclusion, these findings suggest that the bioconversion of apocynin to diapocynin is an important issue not limited to enzymatic activity inhibition, but also for other biological effects as gp91(phox) mRNA expression and cytokine production. Hence, as diapocynin can be easily prepared from apocynin, a one-step synthesis, we recommend its use in studies where the biological effects of apocynin are searched. (C) 2010 Elsevier Inc. All rights reserved.
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We present the first measurement of photoproduction of J/psi and of two-photon production of high-mass e(+)e(-) pairs in electromagnetic (or ultra-peripheral) nucleus-nucleus interactions, using Au + Au data at root s(NN) = 200 GeV. The events are tagged with forward neutrons emitted following Coulomb excitation of one or both Au* nuclei. The event sample consists of 28 events with m(e+e-) > 2 GeV/c(2) with zero like-sign background. The measured cross sections at midrapidity of d sigma/dy (J/psi + Xn, y = 0) = 76 +/- 33 (stat) +/- 11 (syst) pb and d(2)sigma /dm dy (e(+) e(-) + Xn, y = 0) = 86 +/- 23(stat) +/- 16(syst) mu b/ (GeV/c(2)) for m(e+e-) epsilon vertical bar 2.0, 2.8 vertical bar GeV/c(2) have been compared and found to be consistent with models for photoproduction of J/psi and QED based calculations of two-photon production of e(+)e(-) pairs. (C) 2009 Elsevier B.V. All rights reserved.
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New tetraruthenated manganese (III) porphyrins were synthesized and characterized (P-31 NMR, cyclic voltammetry, UV-Vis). This new system presents four units of cationic ``[RuCl(dppb)(X-bipy)](+)``. The electrochemical and catalytic properties of the central manganese (III) show dependence on the characteristics of the peripheral ruthenium complexes as evidenced by the Mn-(III)/Mn-(II) reduction potential. The catalytic oxidation reactions of olefins, cyclohexene and cyclohexane, were carried out in the presence of tetrapyridyl manganese (III) porphyrins containing cationic ruthenium complex and using iodosylbenzene as oxygen donor. The performance of these new tetraruthenated porphyrins systems were evaluated and compared with the manganese porphyrin. (C) 2007 Elsevier Ltd. All rights reserved.
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Pollinator visitation rates over the life of a flower are determined by pollinator abundance and floral longevity. If flowers are not visited frequently enough, pollen limitation may occur, favoring the evolution of self-compatibility (SC). In plant species with varying SC levels, central populations often are self-incompatible (SI) and peripheral populations are SC. Witheringia solanacea (Solanaceae) is a species that follows this trend with the exception of one population in the Monteverde Cloud Forest Reserve, which is peripheral yet SI. I investigated this population using multiple techniques including floral bagging, pollinator observations, microsatellite analysis, and floral longevity manipulations. My results confirmed the self-incompatibility of the Monteverde population and indicated low but perhaps adequate rates of pollinator visitation per flower per hour. I found reduced genetic diversity at Monteverde and gene flow occurring unidirectionally from San Luis (a central population) to Monteverde. In the greenhouse, there was more of an effect of male than female function on floral longevity, but the largest differences were environmental. Flowers stayed open substantially longer when cool, cloudy weather was simulated and shorter when conditions were hot and sunny. The results indicate that the Monteverde population of W. solanacea is SI because 1) it is unable to maximize its fitness due to gene flow from San Luis and its relatively recent colonization of the area and 2) pollen limitation may not be severe because of supplemental pollinator availability from other Witheringia species in the area and increased floral longevities due to cool and cloudy conditions.
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Water-insoluble glucan was isolated from the baker’s yeast Saccharomyces cerevisiae. The yeast cells were treated with alkali and the residue then with acid. Chemical and NMR (1D and 2D) analyses showed that a linear (1→3)-β-glucan was purified that was not contaminated with other carbohydrates, proteins or phenolic compounds. The effects of the glucan on wound healing were assessed in human venous ulcers by histopathological analysis after 30 days of topical treatment. (1→3)-β-glucan enhanced ulcer healing and increased epithelial hyperplasia, as well as increased inflammatory cells, angiogenesis and fibroblast proliferation. In one patient who had an ulcer that would not heal for over 15 years, glucan treatment caused a 67.8% decrease in the area of the ulcer. This is the first study to investigate the effects of (1→3)-β-glucan on venous ulcer healing in humans; our findings suggest that this glucan is a potential natural biological response modifier in wound healing
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Water-insoluble glucan was isolated from the baker’s yeast Saccharomyces cerevisiae. The yeast cells were treated with alkali and the residue then with acid. Chemical and NMR (1D and 2D) analyses showed that a linear (1→3)-β-glucan was purified that was not contaminated with other carbohydrates, proteins or phenolic compounds. The effects of the glucan on wound healing were assessed in human venous ulcers by histopathological analysis after 30 days of topical treatment. (1→3)-β-glucan enhanced ulcer healing and increased epithelial hyperplasia, as well as increased inflammatory cells, angiogenesis and fibroblast proliferation. In one patient who had an ulcer that would not heal for over 15 years, glucan treatment caused a 67.8% decrease in the area of the ulcer. This is the first study to investigate the effects of (1→3)-β-glucan on venous ulcer healing in humans; our findings suggest that this glucan is a potential natural biological response modifier in wound healing
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The effects of age on microbiota composition, gut fermentation end-product formation and peripheral lymphocyte numbers were compared between old and young adult Beagle dogs fed four kibble diets differing in yeast cell wall contents. The experiment had a double 4 x 4 Latin square design, one with four mature dogs (4 years old) and the other with four old dogs (10 years old), with four replicates (diets) per dog. In each period a 15d adaptation period preceded a 5d total collection of faeces for the digestibility trial. on day 21, fresh faecal samples were collected for the determination of bacterial enumeration, pH, biogenic amine and short-chain fatty acid. Flow cytometry was used for immunophenotypic evaluation. Dogs were fed four kibble diets with similar composition with 0, 0.15, 0.30 and 0.45% of yeast cell wall (as-fed), respectively. Data were evaluated using general linear models of Statistical Analysis Systems statistical software (P<0.05). No evidence of a difference in faecal bacteria counts between ages was found (total aerobes, total anaerobes, Bifidobacterium, Lactobacillus, Clostridium and Escherichia coli: P. 0.15). Faecal concentrations of butyrate, histamine, agmatine and spermine were lower (P <= 0.05) and faecal pH was higher (P=0.03) in older dogs than in mature adult dogs, suggesting an alteration in bacterial metabolic activity, or in the rate of intestinal absorption of these compounds. Concentrations of T-lymphocytes, T-cytotoxic lymphocytes and B-lymphocytes were also lower (P <= 0.01) in older dogs than in mature adult dogs. The study confirmed alterations in peripheral lymphocytes and revealed a reduced concentration of some fermentation end products in the colon of old dogs.
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Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP)
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Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP)
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Synbranchus marmoratus is a facultative air-breathing fish, which uses its buccal cavity as well as its gills for air-breathing. S. marmoratus shows a very pronounced tachycardia when it surfaces to air-breathe. An elevation of heart rate decreases cardiac filling time and therefore may cause a decline in stroke volume (VS), but this can be compensated for by an increase in venous tone to maintain stroke volume. Thus, the study on S. marmoratus was undertaken to investigate how stroke volume and venous function are affected during air-breathing. To this end we measured cardiac output (Q), heart rate (fH), central venous blood pressure (PCV), mean circulatory filling pressure (MCFP), and dorsal aortic blood pressures (PDA) in S. marmoratus. Measurements were performed in aerated water (P-O2 > 130 mmHg), when the fish alternated between gill ventilation and prolonged periods of apnoeas, as well as during hypoxia (P-O2 <= 50 mmHg), when the fish changed from gill ventilation to air-breathing. Q increased significantly during gill ventilation compared to apnoea in aerated water through a significant increase in both fH and VS. PCV and MCFP also increased significantly. During hypoxia, when the animals surface to ventilate air, we found a marked rise in fH, PCV, MCFP, Q and VS, whereas PDA decreased significantly. Simultaneous increases in PCV and MCFP in aerated, as well as in hypoxic water, suggests that the venous system plays an important regulatory role for cardiac filling and VS in this species. In addition, we investigated adrenergic regulation of the venous system through bolus infusions of adrenergic agonists (adrenaline, phenylephrine and isoproterenol; 2 mu g kg(-1)). Adrenaline and phenylephrine caused a marked rise in PCV and MCFP, whereas isoproterenol led to a marked decrease in PCV, and tended to decrease MCFP. Thus, it is evident that stimulation of both alpha- and beta-adrenoreceptors affects venous tone in S. marmoratus.
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The effects of adrenergic stimulation on mean circulatory filling pressure (MCFP), central venous pressure (P-CV) and stroke volume (Vs), as well as the effects of altered MCFP through changes of blood volume were investigated in rattlesnakes (Crotalus durissus). MCFP is an estimate of the upstream pressure driving blood towards the heart and is determined by blood volume and the activity of the smooth muscle cells in the veins (venous tone). MCFP can be determined as the plateau in P-CV during a total occlusion of blood flow from the heart.Vs decreased significantly when MCFP was lowered by reducing blood volume in anaesthetised snakes, whereas increased MCFP through infusion of blood (up to 3 ml kg(-1)) only led to a small rise in Vs. Thus, it seems that end-diastolic volume is not affected by an elevated MCFP in rattlesnakes. To investigate adrenergic regulation on venous tone, adrenaline as well as phenylephrine and isoproterenol (alpha- and beta-adrenergic agonists, respectively) were infused as bolus injections (2 and 10 mu g kg(-1)). Adrenaline and phenylephrine caused large increases in MCFP and P-CV, whereas isoproterenol decreased both parameters. This was also the case in fully recovered snakes. Therefore, adrenaline affects venous tone through both alpha- and beta-adrenergic receptors, but the alpha-adrenergic receptor dominates at the dosages used in the present study. Injection of the nitric oxide donor SNP caused a significant decrease in P-CV and MCFP. Thus, nitric oxide seems to affect venous tone.
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A Neuropatia diabética periférica (NDP) cursa com redução somatossensitiva que pode levar a alterações no controle postural. O objetivo do estudo foi avaliar o controle postural na postura ereta, em diferentes condições, e o equilíbrio funcional em indivíduos com NDP, correlacionar os resultados obtidos na avaliação do controle postural com os valores do teste do equilíbrio funcional e comparar os resultados obtidos no grupo neuropata com o grupo controle, verificando as possíveis diferenças entre as condições de avaliação em ambos os grupos. Participaram do estudo 13 mulheres com NDP (GN) e 17 mulheres não diabéticas (GC). A avaliação do controle postural foi realizada por cinemetria nas condições: olhos abertos (OA), olhos fechados (OF) e semi tandem (ST). Após processamento no MATLAB, foram geradas as variáveis: amplitude média de oscilação (AMO) na direção ântero-posterior (AP) e médio-lateral (ML); e velocidade média de oscilação (VMO) na direção AP e ML. O equilíbrio funcional foi avaliado pelo Timed Up and Go Test. Houve diferença significante entre os grupos (p<0,005) na AMO-AP OA e OF, AMO-ML of e ST e VMO-ML ST. Houve diferença entre as condições OA e ST (p<0,005) e of e ST (p<0,005) para as variáveis AMO-ML e VMO-ML, com maior prejuízo para o GN, que também apresentou um menor equilíbrio funcional (p=0,001). A instabilidade ML foi correlacionada positivamente com o desequilíbrio funcional. Os resultados nos mostram uma alteração no sistema de controle postural na NDP, o que pode levar estes indivíduos a um maior risco a quedas e prejuízos funcionais.