60 resultados para systemic effects


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BACKGROUND: Fish oil (FO) has antiinflammatory effects, which might reduce systemic inflammation induced by a cardiopulmonary bypass (CPB). OBJECTIVE: We tested whether perioperative infusions of FO modify the cell membrane composition, inflammatory responses, and clinical course of patients undergoing elective coronary artery bypass surgery. DESIGN: A prospective randomized controlled trial was conducted in cardiac surgery patients who received 3 infusions of 0.2 g/kg FO emulsion or saline (control) 12 and 2 h before and immediately after surgery. Blood samples (7 time points) and an atrial biopsy (during surgery) were obtained to assess the membrane incorporation of PUFAs. Hemodynamic data, catecholamine requirements, and core temperatures were recorded at 10-min intervals; blood triglycerides, nonesterified fatty acids, glucose, lactate, inflammatory cytokines, and carboxyhemoglobin concentrations were measured at selected time points. RESULTS: Twenty-eight patients, with a mean ± SD age of 65.5 ± 9.9 y, were enrolled with no baseline differences between groups. Significant increases in platelet EPA (+0.86%; P = 0.0001) and DHA (+0.87%; P = 0.019) were observed after FO consumption compared with at baseline. Atrial tissue EPA concentrations were higher after FO than after control treatments (+0.5%; P < 0.0001). FO did not significantly alter core temperature but decreased the postoperative rise in IL-6 (P = 0.018). Plasma triglycerides increased transiently after each FO infusion. Plasma concentrations of glucose, lactate, and blood carboxyhemoglobin were lower in the FO than in the control group on the day after surgery. Arrhythmia incidence was low with no significant difference between groups. No adverse effect of FO was detected. CONCLUSIONS: Perioperative FO infusions significantly increased PUFA concentrations in platelet and atrial tissue membranes within 12 h of the first FO administration and decreased biological and clinical signs of inflammation. These results suggest that perioperative FO may be beneficial in elective cardiac surgery with CPB. This trial was registered at clinicaltrials.gov as NCT00516178.

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OBJECTIVE: To analyze the cardiovascular effects of sodium bicarbonate in neonates with metabolic acidosis. DESIGN: Prospective, open, non-randomized, before-after intervention study with hemodynamic measurements performed before and 1, 5, 10, 20, and 30 min after bicarbonate administration. SETTING: Neonatal intensive care unit, tertiary care center. PATIENTS: Sequential sample of 16 paralysed and mechanically ventilated newborn infants with a metabolic acidosis (pH < 7.25 in premature and < 7.30 in term infants, base deficit > -8). INTERVENTION: An 8.4% sodium bicarbonate solution diluted 1:1 with water (final osmolality of 1000 mOsm/l) was administered in two equal portions at a rate of 0.5 mmol/min. The dose in mmol was calculated using the formula "base deficit x body weight (kg) x 1/3 x 1/2". MEASUREMENTS AND RESULTS: Sodium bicarbonate induced a significant but transient rise in pulsed Doppler cardiac output (CO) (+27.7%), aortic blood flow velocity (+15.3%), systolic blood pressure (BP) (+9.3%), (+14.6%), transcutaneous carbon dioxide pressure (PtcCO2) (+11.8%), and transcutaneous oxygen pressure (PtcO2) (+8%). In spite of the PaCO2 elevation, pH significantly improved (from a mean of 7.24 to 7.30), and the base deficit decreased (-39.3%). Calculated systemic vascular resistance (SVR) (-10.7%) and diastolic BP (-11.7%) decreased significantly, while PaO2 and heart rate (HR) did not change. Central venous pressure (CVP) (+6.5%) increased only slightly. By 30 min after bicarbonate administration all hemodynamic parameters, with the exception of the diastolic BP, had returned to baseline. CONCLUSION: Sodium bicarbonate in neonates with metabolic acidosis induces an increase in contractility and a reduction in afterload.

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Primary systemic amyloidosis (AL amyloidosis) continues to have a very poor prognosis. Most therapeutic strategies remain unsatisfactory. Conventional chemotherapy is known to offer at best only moderate efficacy. Several studies have yielded higher complete response rates after high-dose chemotherapy and autologous stem cell transplantation (ASCT) in addition to improving outcomes in a subgroup of patients. However, the superiority of an intensive approach in AL amyloidosis has not been confirmed in a randomised trial. The precise role of ASCT remains unclear. We report our experience in 16 patients diagnosed with AL amyloidosis and treated in a multidisciplinary approach with high-dose melphalan and ASCT. Median age was 59 (39-71) years. The kidneys were predominantly affected in 75% of cases; two or more organs were affected in 38%. Median time from diagnosis to transplantation was 2 (1-4) months. Three patients (19%) developed acute renal failure and required transient dialysis. Transplant-related mortality was 6% after 100 days. Haematological complete response (CR) was obtained in nine (56%) and organ response in six (38%) patients. Nine out of 12 patients (75%) with kidney involvement exhibited a sustained clinical benefit at 12 months. Half of all the patients (n = 8) were alive after a median follow-up of 33 months, including two in continuous CR. This suggests that high-dose chemotherapy and ASCT are still valid treatment options in AL amyloidosis and that a significant number of patients with renal involvement might benefit from this approach.

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INTRODUCTION: Osteoset(®) T is a calcium sulphate void filler containing 4% tobramycin sulphate, used to treat bone and soft tissue infections. Despite systemic exposure to the antibiotic, there are no pharmacokinetic studies in humans published so far. Based on the observations made in our patients, a model predicting tobramycin serum levels and evaluating their toxicity potential is presented. METHODS: Following implantation of Osteoset(®) T, tobramycin serum concentrations were monitored systematically. A pharmacokinetic analysis was performed using a non-linear mixed effects model based on a one compartment model with first-degree absorption. RESULTS: Data from 12 patients treated between October 2006 and March 2008 were analysed. Concentration profiles were consistent with the first-order slow release and single-compartment kinetics, whilst showing important variability. Predicted tobramycin serum concentrations depended clearly on both implanted drug amount and renal function. DISCUSSION AND CONCLUSION: Despite the popularity of aminoglycosides for local antibiotic therapy, pharmacokinetic data for this indication are scarce, and not available for calcium sulphate as carrier material. Systemic exposure to tobramycin after implantation of Osteoset(®) T appears reassuring regarding toxicity potential, except in case of markedly impaired renal function. We recommend in adapting the dosage to the estimated creatinine clearance rather than solely to the patient's weight.

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The effects of the sympathetic activation elicited by a mental stress on insulin sensitivity and energy expenditure (VO(2)) were studied in 11 lean and 8 obese women during a hyperinsulinemic-euglycemic clamp. Six lean women were restudied under nonselective beta-adrenergic blockade with propranolol to determine the role of beta-adrenoceptors in the metabolic response to mental stress. In lean women, mental stress increased VO(2) by 20%, whole body glucose utilization ([6,6-(2)H(2)]glucose) by 34%, and cardiac index (thoracic bioimpedance) by 25%, whereas systemic vascular resistance decreased by 24%. In obese women, mental stress increased energy expenditure as in lean subjects, but it neither stimulated glucose uptake nor decreased systemic vascular resistance. In the six lean women who were restudied under propranolol, the rise in VO(2), glucose uptake, and cardiac output and the decrease in systemic vascular resistance during mental stress were all abolished. It is concluded that 1) in lean subjects, mental stress stimulates glucose uptake and energy expenditure and produces vasodilation; activation of beta-adrenoceptors is involved in these responses; and 2) in obese patients, the effects of mental stress on glucose uptake and systemic vascular resistance, but not on energy expenditure, are blunted.

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BACKGROUND: Particulate air pollution is associated with increased risk of cardiovascular disease and stroke. Although the precise mechanisms underlying this association are still unclear, the induction of systemic inflammation following particle inhalation represents a plausible mechanistic pathway.¦METHODS: We used baseline data from the CoLaus Study including 6183 adult participants residing in Lausanne, Switzerland. We analyzed the association of short-term exposure to PM10 (on the day of examination visit) with continuous circulating serum levels of high-sensitive C-reactive protein (hs-CRP), interleukin 1-beta (IL-1β), interleukin 6 (IL-6), and tumor-necrosis-factor alpha (TNF-α) by robust linear regressions, controlling for potential confounding factors and assessing effect modification.¦RESULTS: In adjusted analyses, for every 10 μg/m3 elevation in PM10, IL-1ß increased by 0.034 (95 % confidence interval, 0.007-0.060) pg/mL, IL-6 by 0.036 (0.015-0.057) pg/mL, and TNF-α by 0.024 (0.013-0.035) pg/mL, whereas no significant association was found with hs-CRP levels.¦CONCLUSIONS: Short-term exposure to PM10 was positively associated with higher levels of circulating IL-1ß, IL-6 and TNF-α in the adult general population. This positive association suggests a link between air pollution and cardiovascular risk, although further studies are needed to clarify the mechanistic pathway linking PM10 to cardiovascular risk.

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Phosphate is a crucial and often limiting nutrient for plant growth. To obtain inorganic phosphate (P(i) ), which is very insoluble, and is heterogeneously distributed in the soil, plants have evolved a complex network of morphological and biochemical processes. These processes are controlled by a regulatory system triggered by P(i) concentration, not only present in the medium (external P(i) ), but also inside plant cells (internal P(i) ). A 'split-root' assay was performed to mimic a heterogeneous environment, after which a transcriptomic analysis identified groups of genes either locally or systemically regulated by P(i) starvation at the transcriptional level. These groups revealed coordinated regulations for various functions associated with P(i) starvation (including P(i) uptake, P(i) recovery, lipid metabolism, and metal uptake), and distinct roles for members in gene families. Genetic tools and physiological analyses revealed that genes that are locally regulated appear to be modulated mostly by root development independently of the internal P(i) content. By contrast, internal P(i) was essential to promote the activation of systemic regulation. Reducing the flow of P(i) had no effect on the systemic response, suggesting that a secondary signal, independent of P(i) , could be involved in the response. Furthermore, our results display a direct role for the transcription factor PHR1, as genes systemically controlled by low P(i) have promoters enriched with P1BS motif (PHR1-binding sequences). These data detail various regulatory systems regarding P(i) starvation responses (systemic versus local, and internal versus external P(i) ), and provide tools to analyze and classify the effects of P(i) starvation on plant physiology.

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PURPOSE: To evaluate the safety and efficacy of an intravitreal fluocinolone acetonide (FA) implant compared with standard therapy in subjects with noninfectious posterior uveitis (NIPU). DESIGN: Randomized, controlled, phase 2b/3, open-label, multicenter superiority trial. PARTICIPANTS: Subjects with unilateral or bilateral NIPU. METHODS: One hundred forty subjects received either a 0.59-mg FA intravitreal implant (n = 66) or standard of care (SOC; n = 74) with either systemic prednisolone or equivalent corticosteroid as monotherapy (> or =0.2 mg/kg daily) or, if judged necessary by the investigator, combination therapy with an immunosuppressive agent plus a lower dose of prednisolone or equivalent corticosteroid (> or =0.1 mg/kg daily). MAIN OUTCOME MEASURES: Time to first recurrence of uveitis. RESULTS: Eyes that received the FA intravitreal implant experienced delayed onset of observed recurrence of uveitis (P<0.01) and a lower rate of recurrence of uveitis (18.2% vs. 63.5%; P< or =0.01) compared with SOC study eyes. Adverse events frequently observed in implanted eyes included elevated intraocular pressure (IOP) requiring IOP-lowering surgery (occurring in 21.2% of implanted eyes) and cataracts requiring extraction (occurring in 87.8% of phakic implanted eyes). No treatment-related nonocular adverse events were observed in the implant group, whereas such events occurred in 25.7% of subjects in the SOC group. CONCLUSIONS: The FA intravitreal implant provided better control of inflammation in patients with uveitis compared with systemic therapy. Intraocular pressure and lens clarity of implanted eyes need close monitoring in patients receiving the FA intravitreal implant.

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OBJECTIVE: We developed interferon-α-kinoid (IFN-K), a drug composed of inactivated IFNα coupled to a carrier protein, keyhole limpet hemocyanin. In human IFNα-transgenic mice, IFN-K induces polyclonal antibodies that neutralize all 13 subtypes of human IFNα. We also previously demonstrated that IFN-K slows disease progression in a mouse model of systemic lupus erythematosus (SLE). This study was undertaken to examine the safety, immunogenicity, and biologic effects of active immunization with IFN-K in patients with SLE. METHODS: We performed a randomized, double-blind, placebo-controlled, phase I/II dose-escalation study comparing 3 or 4 doses of 30 μg, 60 μg, 120 μg, or 240 μg of IFN-K or placebo in 28 women with mild to moderate SLE. RESULTS: IFN-K was well tolerated. Two SLE flares were reported as serious adverse events, one in the placebo group and the other in a patient who concomitantly stopped corticosteroids 2 days after the first IFN-K dose, due to mild fever not related to infection. Transcriptome analysis was used to separate patients at baseline into IFN signature-positive and -negative groups, based on the spontaneous expression of IFN-induced genes. IFN-K induced anti-IFNα antibodies in all immunized patients. Notably, significantly higher anti-IFNα titers were found in signature-positive patients than in signature-negative patients. In IFN signature-positive patients, IFN-K significantly reduced the expression of IFN-induced genes. The decrease in IFN score correlated with the anti-IFNα antibody titer. Serum complement C3 levels were significantly increased in patients with high anti-IFNα antibody titers. CONCLUSION: These results show that IFN-K is well tolerated, immunogenic, and significantly improves disease biomarkers in SLE patients, indicating that further studies of its clinical efficacy are warranted.

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The low GFR of newborns is maintained by various factors including the renin-angiotensin system. We previously established the importance of angiotensin II in the newborn kidney, using the angiotensin-converting enzyme inhibitor perindoprilat. The present study was designed to complement these observations by evaluating the role of angiotensin-type 1 (AT(1)) receptors, using losartan, a specific AT(1)-receptor blocker. Increasing doses of losartan were infused into anesthetized, ventilated, newborn rabbits. Renal function and hemodynamic variables were assessed using inulin and para-aminohippuric acid clearances as markers of GFR and renal plasma flow, respectively. Losartan 0.1 mg/kg slightly decreased mean blood pressure (-11%) and increased diuresis (+22%). These changes can be explained by inhibition of the AT(1)-mediated vasoconstrictive and antidiuretic effects of angiotensin, and activation of vasodilating and diuretic AT(2) receptors widely expressed in the neonatal period. GFR and renal blood flow were not modified. Losartan 0.3 mg/kg decreased mean blood pressure significantly (-15%), probably by inhibiting systemic AT(1) receptors. GFR significantly decreased (-25%), whereas renal blood flow remained stable. The decrease in filtration fraction (-21%) indicates predominant efferent vasodilation. At 3 mg/kg, the systemic hypotensive effect of losartan was marked (mean blood pressure, -28%), with decreased GFR and renal blood flow (-57% and -51%, respectively), a stable filtration fraction, and an increase in renal vascular resistance by 124%. The renal response to this dose can be considered as reflex vasoconstriction of afferent and efferent arterioles, rather than specific receptor antagonism. We conclude that under physiologic conditions, the renin-angiotensin is critically involved in the maintenance of GFR in the immature kidney.

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Summary: Particulate air pollution is associated with increased cardiovascular risk. The induction of systemic inflammation following particle inhalation represents a plausible mechanistic pathway. The purpose of this study was to assess the associations of short-term exposure to ambient particulate matters of aerodynamic diameter less than 10 μm (PM10) with circulating inflammatory markers in 6183 adults in Lausanne, Switzerland. The results show that short-term exposure to PM10 was associated with higher levels of circulating IL-6 and TNF-α. The positive association of PM10 with markers of systemic inflammation materializes the link between air pollution and cardiovascular risk. Background: Variations in short-term exposure to particulate matters (PM) have been repeatedly associated with daily all-cause mortality. Particle-induced inflammation has been postulated to be one of the important mechanisms for increased cardiovascular risk. Experimental in-vitro, in-vivo and controlled human studies suggest that interleukin 6 (IL-6) and tumor-necrosis-factor alpha (TNF-α) could represent key mediators of the inflammatory response to PM. The associations of short-term exposure to ambient PM with circulating inflammatory markers have been inconsistent in studies including specific subgroups so far. The epidemiological evidence linking short-term exposure to ambient PM and systemic inflammation in the general population is scarce. So far, large-scale population-based studies have not explored important inflammatory markers such as IL-6, IL-1β or TNF-α. We therefore analyzed the associations between short-term exposure to ambient PM10 and circulating levels of high-sensitive CRP (hs-CRP), IL-6, IL-1β and TNF-α in the population-based CoLaus study. Objectives: To assess the associations of short-term exposure to ambient particulate matters of aerodynamic diameter less than 10 μm (PM10) with circulating inflammatory markers, including hs-CRP, IL-6, IL-1β and TNF-α, in adults aged 35 to 75 years from the general population. Methodology: All study subjects were participants to the CoLaus study (www.colaus.ch) and the baseline examination was carried out from 2003 to 2006. Overall, 6184 participants were included. For the present analysis, 6183 participants had data on at least one of the four measured circulating inflammatory markers. The monitoring data was obtained from the website of Swiss National Air Pollution Monitoring Network (NABEL). We analyzed data on PM10 as well as outside air temperature, pressure and humidity. Hourly concentrations of PM10 were collected from 1 January 2003 to 31 December 2006. Robust linear regression (PROC ROBUSTREG) was used to evaluate the relationship between cytokine inflammatory and PM10. We adjusted all analyses for age, sex, body mass index, smoking status, alcohol consumption, diabetes status, hypertension status, education levels, zip code, and statin intake. All data were adjusted for the effects of weather by including temperature, barometric pressure, and season as covariates in the adjusted models. We performed simple and multiple logistic regression analyses. Descriptive statistical analysis used the Wilcoxon rank sum test (for medians). All data analyses were performed using SAS software (version 9.2; SAS Institute Inc., Cary, NC, USA), and a two-sided significance level of 5% was used. Results: PM10 levels averaged over 24 hours were significantly and positively associated with continuous IL-6 and TNF-α levels, in the whole study population both in unadjusted and adjusted analyses. For each cytokine, there was a similar seasonal pattern, with wider confidence intervals in summer than during the other seasons, which might partly be due to the smaller number of participants examined in summer. The associations of PM10 with IL-6 and TNF-α were also found after having dichotomized these cytokines into high versus low levels, which suggests that the associations of PM10 with the continuous cytokine levels are very robust to any distributional assumption and to potential outlier values. In contrast with what we observed for continuous IL-1β levels, high PM10 levels were significantly associated with high IL-1β. PM10 was significantly associated with IL-6 and TNF-α in men, but with TNF-α only in women. However, there was no significant statistical interaction between PM10 and sex. For IL-6 and TNF-α, the associations tended to be stronger in younger people, with a significant interaction between PM10 and age groups for IL-6. PM10 was significantly associated with IL-6 and TNF-α in the healthy group and also in the "non-healthy" group, although the statistical interaction between healthy status and PM10 was not significant. Conclusion: In summary, we found significant independent positive associations of short-term exposure to PM10 with circulating levels of IL-6 and TNF-α in the adult population of Lausanne. Our findings strongly support the idea that short-term exposure to PM10 is sufficient to induce systemic inflammation on a broad scale in the general population. From a public health perspective, the reported association of elevated inflammatory cytokines with short-term exposure to PM10 in a city with relatively clean air such as Lausanne supports the importance of limiting urban air pollution levels.

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PURPOSE: Low tidal volume ventilation and permissive hypercapnia are required in patients with sepsis complicated by ARDS. The effects of hypercapnia on tissue oxidative metabolism in this setting are unknown. We therefore determined the effects of moderate hypercapnia on markers of systemic and splanchnic oxidative metabolism in an animal model of endotoxemia. METHODS: Anesthetized rats maintained at a PaCO(2) of 30, 40 or 60 mmHg were challenged with endotoxin. A control group (PaCO(2) 40 mmHg) received isotonic saline. Hemodynamic variables, arterial lactate, pyruvate, and ketone bodies were measured at baseline and after 4 h. Tissue adenosine triphosphate (ATP) and lactate were measured in the small intestine and the liver after 4 h. RESULTS: Endotoxin resulted in low cardiac output, increased lactate/pyruvate ratio and decreased ketone body ratio. These changes were not influenced by hypercapnia, but were more severe with hypocapnia. In the liver, ATP decreased and lactate increased independently from PaCO(2) after endotoxin. In contrast, the drop of ATP and the rise in lactate triggered by endotoxin in the intestine were prevented by hypercapnia. CONCLUSIONS: During endotoxemia in rats, moderate hypercapnia prevents the deterioration of tissue energetics in the intestine.

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The mammalian circadian timing system consists of a central pacemaker in the brain's suprachiasmatic nucleus (SCN) and subsidiary oscillators in nearly all body cells. The SCN clock, which is adjusted to geophysical time by the photoperiod, synchronizes peripheral clocks through a wide variety of systemic cues. The latter include signals depending on feeding cycles, glucocorticoid hormones, rhythmic blood-borne signals eliciting daily changes in actin dynamics and serum response factor (SRF) activity, and sensors of body temperature rhythms, such as heat shock transcription factors and the cold-inducible RNA-binding protein CIRP. To study these systemic signalling pathways, we designed and engineered a novel, highly photosensitive apparatus, dubbed RT-Biolumicorder. This device enables us to record circadian luciferase reporter gene expression in the liver and other organs of freely moving mice over months in real time. Owing to the multitude of systemic signalling pathway involved in the phase resetting of peripheral clocks the disruption of any particular one has only minor effects on the steady state phase of circadian gene expression in organs such as the liver. Nonetheless, the implication of specific pathways in the synchronization of clock gene expression can readily be assessed by monitoring the phase-shifting kinetics using the RT-Biolumicorder.