972 resultados para Blood volume expansion
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Objective and design: Knowing that hyperglycemia is a hallmark of vascular dysfunction in diabetes and that neonatal streptozotocin-induced diabetic rats (n-STZ) present reduced inflammatory response, we decided to evaluate the effect of chlorpropamide-lowered blood glucose levels on carrageenan-induced rat paw edema and pleural exudate in n-STZ. Materials: Diabetes was induced by STZ injection (160 mg/kg, ip) in neonates (2-day-old) Wistar rats. Treatment: n-STZ diabetic rats were treated with chlorpropamide (200 mg/kg, 15 d, by gavage) 8 weeks after STZ injection. Methods: Carrageenan-induced paw edema and pleural exudate volumes were assessed concomitantly with peripheral and exudate leukocyte count. We also evaluated the expression of inducible nitric oxide synthase (iNOS) in lungs of all experimental groups. Results: Chlorpropamide treatment improved glucose tolerance, beta-cell function (assessed by HOMA-beta), corrected paw edema, and pleural exudate volume in n-STZ. Neither leukocyte count nor iNOS expression were affected by diabetes or by chlorpropamide treatment. Conclusion: Chlorpropamide treatment by restoring beta-cell function, reducing blood sugar levels, and improving glucose tolerance might be contributing to the correction of the reduced inflammatory response tested as paw edema and pleural exudate in n-STZ diabetic rats.
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Recent advances in the field of chaotic advection provide the impetus to revisit the dynamics of particles transported by blood flow in the presence of vessel wall irregularities. The irregularity, being either a narrowing or expansion of the vessel, mimicking stenoses or aneurysms, generates abnormal flow patterns that lead to a peculiar filamentary distribution of advected particles, which, in the blood, would include platelets. Using a simple model, we show how the filamentary distribution depends on the size of the vessel wall irregularity, and how it varies under resting or exercise conditions. The particles transported by blood flow that spend a long time around a disturbance either stick to the vessel wall or reside on fractal filaments. We show that the faster flow associated with exercise creates widespread filaments where particles can get trapped for a longer time, thus allowing for the possible activation of such particles. We argue, based on previous results in the field of active processes in flows, that the non-trivial long-time distribution of transported particles has the potential to have major effects on biochemical processes occurring in blood flow, including the activation and deposition of platelets. One aspect of the generality of our approach is that it also applies to other relevant biological processes, an example being the coexistence of plankton species investigated previously.
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AZEVEDO, George Dantas de et al. Raloxifene therapy does not affect uterine blood flow in postmenopausal women: a transvaginal Doppler study. Maturitas, Amsterdam, v.47, n.3, p.195-200, 2004
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Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP)
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Trasnversal study, with the objective of evaluating the accuracy of clinical indicators of nursing diagnosis excessive fluid volume in patients undergoing hemodialysis. The study occurred in two stages, the first consisted of the evaluation of the diagnostic indicators in study; and the second, the diagnostic inference conducted by nurse diagnosticians. The first stage occurred from december 2012 to april 2013, in a University Hospital and a Hemodialysis Clinic in Northeastern of Brazil, with a sample of 100 chronic renal failure patients on hemodialysis. The data were selected through an interview form and a physical examination, organized into spreadsheets and analyzed as to the presence or absence of the indicators of diagnosis excessive fluid volume. In the second step, the spreadsheets were sent to three nurses diagnosticians, who judged the presence or absence of diagnosis in the clientele searched. This step was conducted from july to september 2013. For analysis of the data, we used descriptive and inferential statistics. In the descriptive analysis, we used measures of central tendency and dispersion. In inferential analysis, we used the tests Chi- square, Fisher and prevalence ratios. The accuracy of the clinical indicators pertaining to the diagnosis were measured as to the specificity, sensitivity, predictive values, likelihood ratios and Diagnostic Odds Ratio. Also developed a logistic regression. The results were organized in tables and discussed with literature. This study was approved by the Ethics Committee in Research of the Federal University of Rio Grande do Norte, with Presentation Certificate for Ethics Appreciation nº 08696212.7.0000.5537. The results revealed that the diagnosis studied was present in 82% of patients. The characteristics with prevalence above 50 % that stood out were: azotemia, decreased hematocrit, electrolyte imbalance, intake exceeds output, anxiety, edema, decreased hemoglobin, oliguria and blood pressure changes. Eight defining characteristics were presented statistically significant association with the nursing diagnosis investigated: pulmonary congestion, intake exceeds output, electrolytes imbalance, jugular vein distension, edema, weight gain over short period of time, agitation and adventitious breath sounds. Among these, the 10 characteristics which showed higher prevalence ratios were: edema and weight gain over short period of time. The features with the highest sensitivity were edema, electrolytes imbalance and intake exceeds output and the standing out with greater specificity were: anasarca, weight gain over short period of time, change in respiratory pattern, adventitious breath sounds, pulmonary congestion, agitation and jugular vein distension. The indicators jugular vein distension, electrolytes imbalance, intake exceeds output, increased central venous pressure and edema, together, were identified in the logistic regression model as the most significant predictors. It is concluded that the identification of accurate clinical indicators allow a good prediction of the nursing diagnosis of excessive fluid volume in patients undergoing hemodialysis in order to assist the nurse in the inference process, which will contribute to the success of patient care. In addition, nurses will consider for diagnostic inference not only his clinical experience, but also scientific evidence of the occurrence of excessive fluid volume, contributing to the control of volemia in these patients
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The experiment was conducted to evaluate the effect of feed restriction and different sodium levels in the diet on the performance and hematological values (erythrocyte, hemoglobin, hematocrit, mean cell volume, mean cell hemoglobin, mean cell hemoglobin concentration and white blood cell) of broilers from 22 to 42 days of age. A completely randomized design was used in a 4 x 2 x 2 factorial (levels of sodium: 0.16%, 0.19%, 0.22% and 0.25%; with or without feed restriction; male and female), and two replicates of thirty broilers each. Sodium levels did not affect performance (p>0.05). Feed restriction resulted in increased feed intake and affected weight gain and feed conversion negatively (p<0.05). Better weight gain and feed conversion (p<0.05) were seen in male broilers. Hematological values were not affected by sodium levels, feed restriction or sex (p>0.05).
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JUSTIFICATIVA E OBJETIVOS: Não existem estudos que associem os efeitos determinados pelas modalidades ventilatórias às repercussões hemodinâmicas durante o pneumoperitônio. O objetivo deste estudo foi avaliar as alterações na hemodinâmica determinadas pelo pneumoperitônio em cães com ventilação por volume e pressão controlados. MÉTODO: Dezesseis cães anestesiados com tiopental sódico e fentanil foram divididos em grupo 1, volume controlado, e grupo 2, pressão controlada, e submetidos ao pneumoperitônio de 10 e 15 mmHg. Foram estudados freqüência cardíaca, pressão arterial média, pressão de átrio direito, pressão de artéria pulmonar ocluída, índice cardíaco, índice de resistência vascular sistêmica e vasopressina plasmática. Os dados foram coletados em 4 momentos. M1 - antes do pneumoperitônio, M2 - 30 minutos após pneumoperitônio com 10 mmHg, M3 - 30 minutos após pneumoperitônio com 15 mmHg, M4 - 30 minutos após a deflação do pneumoperitônio. RESULTADOS: Os resultados mostraram aumento no índice cardíaco, nas pressões de átrio direito e de artéria pulmonar ocluída em M2 e M3, em ambos os grupos. A vasopressina não variou durante o procedimento e o índice de resistência vascular sistêmica não aumentou, proporcionando estabilidade da pressão arterial média em ambos os grupos. CONCLUSÕES: As modalidades ventilatórias não determinaram diferenças na resposta hemodinâmica entre os grupos estudados. A técnica anestésica utilizada e as pressões intra-abdominais alcançadas determinaram estabilidade da pressão arterial média, provavelmente decorrente da ausência do aumento no índice da resistência vascular sistêmica.
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Coordenação de Aperfeiçoamento de Pessoal de Nível Superior (CAPES)
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The aim this study was to evaluate systolic and diastolic function in volume overload induced myocardial hypertrophy in rats.Volume overload myocardial hypertrophy was induced in thirteen male Wistar rats by creating infrarenal arteriovenous fistula (AVF). The results were compared with a SHAM operated group (n = 11). Eight weeks after surgery, tail-cuff blood pressure was recorded, then rats were sacrificed for isolated heart studies using Langendorffs preparation.AVF rats presented increased left and right ventricular weights, compared to controls. The increased normalized ventricular volume (V0/LVW, 0.141 +/- 0.035 mL/g vs. 0.267 +/- 0.071 mL/g, P < 0.001) in the AVF group indicated chamber dilation. Myocardial hydroxyproline concentration remained unchanged. There was a significant decrease in +dP/dt (3318 +/- 352 mm Hg s(-1) vs. 2769 +/- 399 mm Hg s(-1); P=0,002), end-systolic pressure-volume relation (246 +/- 56 mm Hg mL(-1) vs. 114 +/- 63 mm Hg mL(-1);, P < 0,001), and -dP/dt (1746 +/- 240 min Hg s(-1) vs. 1361 +/- 217 mm Hg s(-1), P < 0.001) in the AVF group, which presented increased ventricular compliance (Delta V-25: SHAM=0.172 +/- 0.05 mL vs. AVF=0.321 +/- 0.072 mL, P < 0.001) with preserved myocardial passive stiffness (Strain(25): SHAM=13.5 +/- 3.0% vs. AVF=12.3 +/- 1.9%, P > 0.05).We conclude that volume-overload induced hypertrophy causes myocardial systolic and diastolic dysfunction with increased ventricular compliance. These haemodynamic features help to explain the long-term compensatory phase of chronic volume overload before transition to overt congestive heart failure. (c) 2006 European Society of Cardiology. Published by Elsevier B.V. All rights reserved.
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Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP)
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We investigated the effects of injection into the supraoptic nucleus (SON) of losartanand PD 123319 (nonpeptide AT(1) and AT(2)- angiotensin II [ANG II] receptor antagonists, respectively); d(CH2)(5)-Tyr(Me)-AVP (AVPA; an arginine-vasopressin [AVP] V-1 receptor antagonist), FK 409 (a nitric oxide [NO] donor), and N-W-mtro-(L)-arginine methyl ester ((L)-NAME; an NO synthase inhibitor) oil water intake, sodium chloride 3% (NaCl) intake and arterial blood pressure induced by injection of ANG 11 into the lateral septal area (LSA). Mate Holtzman rats (250-300 g) were implanted with cannulae into SON and LSA unilaterally. The drugs were injected in 0.5 mul over 30-60 s. Controls were injected with a similar volume of 0.15 M NaCl. ANG II was injected at a dose of 10 pmol. ANG II antagonists and AVPA were injected at doses of 80 nmol. FK 409 and (L)-NAME were injected at doses of 20 and 40 mug, respectively. Water and NaCl intake was measured over a 2-h period. Prior administration of losartan into the SON decreased water and NaCl intake induced by injection of ANG II. While there was a decrease in water intake, ANG II-induced NaCl intake was significantly increased following injection of AVPA. FK 409 injection decreased water intake and sodium intake induced by ANG II. L-NAME alone increased water and sodium intake and induced a pressor effect. (L)-NAME-potentiated water and sodium intake induced by ANG II. PD 123319 produced no changes in water or sodium intake induced by ANG II. The prior administration of losartan or AVPA decreased mean arterial pressure (MAP) induced by ANG II. PD 123319 decreased the pressor effect of ANG II to a lesser degree than losartan. FK 409 decreased the pressor effect of ANG II while (L)-NAME potentiated it. These results suggest that both ANG II AT, and AVP V, receptors and NO within the SON may be involved in water intake, NaCl intake and the pressor response were induced by activation of ANG II receptors within the LSA. These results do not support the involvement of LSA AT(2) receptors in the mediation of water and NaCl intake responses induced by ANG II, but influence the pressor response. (C) 2004 Elsevier B.V. All rights reserved.
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Male Holtzman rats weighting 200-250 g were anesthetized with zoletil 50 mg/Kg (tiletamine chloridrate 125,0 mg and zolazepan chloridrate 125,0 mg) into quadriceps muscle and submitted an electrolytic lesion of the lateral hypothalamus (LH) and a stainless steel cannula was implanted into their median preoptic nucleus (MnPO). We investigated the effects of the injection into the (MnPO) of FK 409 (20 mug/0.5 mul), a nitric oxide (NO) donor, and N-W-nitro-L-arginine methyl ester (L-NAME) 40 mug/0.5 mul, a nitric oxide synthase inhibitor (NOSI), on the water and sodium appetite and the natriuretic, diuretic and cardiovascular effects induced by injection of L-NAME and FK 409 injected into MnPO in rats with LH lesions. Controls were injected with a similar volume of 0.15 M NaCl. L-NAME injected into MnPO produced an increase in water and sodium intake and in sodium and urine excretion and increase de mean arterial pressure (MAP). FK 409 injected into MnPO did not produce any change in the hydro electrolytic and cardiovascular parameters in LH-sham and lesioned rats. FK 409 injected before L-NAME attenuated its effects. These data show that electrolytic lesion of the LH reduces fluid and sodium intake as well as sodium and urine excretion, and the pressor effect induced by L-NAME. LH involvement with NO of the MnPO excitatory and inhibitory mechanisms related to water and sodium intake, sodium excretion and cardiovascular control is suggested. (C) 2004 Elsevier B.V. All rights reserved.
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Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP)
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We employ finite elements methods for the approximation of solutions of the Ginzburg-Landau equations describing the deconfinement transition in quantum chromodynamics. These methods seem appropriate for situations where the deconfining transition occurs over a finite volume as in relativistic heavy ion collisions. where in addition expansion of the system and flow of matter are important. Simulation results employing finite elements are presented for a Ginzburg-Landau equation based on a model free energy describing the deconfining transition in pure gauge SU(2) theory. Results for finite and infinite system are compared. (C) 2009 Elsevier B.V. All rights reserved.
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Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP)