Endotoxin Desensitization of Human Mononuclear Cells after Cardiopulmonary Bypass: Role of Humoral Factors

Background: The ability of leukocytes to release proinflammatory cytokines on lipopolysaccharide stimulation in vitro is impaired after cardiopulmonary bypass (CPB). This study tested contribution and interaction of humoral factors in altered leukocyte responsiveness to lipopolysaccharide.

Methods: Whole blood and isolated peripheral-blood mononuclear cells (PBMCs) from 10 patients obtained after induction of anesthesia (T1) and 20 min (T2) and 24 h (T3) after CPB were cultured in the absence or presence of lipopolysaccharide and assessed for release of tumor necrosis factor [alpha] (TNF-[alpha]) and interleukin (IL)-1[beta] and their functional antagonists, IL-1 receptor antagonist (IL-1ra) and IL-10. In addition, dose-response characteristics and interaction of IL-10 and norepinephrine as modulators of TNF-[alpha] release were studied.

Results: Cardiopulmonary bypass induced release of antiinflammatory (T2: IL-10: median 25 pg/ml, 25th-75th percentile 9-42; IL-1ra: median 1,528 pg/ml, 25th-75th percentile 1,075-17,047;P < 0.05 compared with T1) but failed to induce proinflammatory cytokines (T2: TNF-[alpha]: median 0 pg/ml, 25th-75th percentile 0-6; IL-1[beta]: median 1 pg/ml, 25th-75th percentile 0-81; nonsignificant). Removal of plasma at T2 increased TNF-[alpha] response to lipopolysaccharide (+83.8%;P < 0.05), whereas it suppressed IL-10 (-36.8%;P < 0.05). Similarly, incubation of PBMCs (T1) with plasma obtained after CPB (T2) as well as addition of IL-10 or norepinephrine in concentrations present in plasma after CPB led to a reduced lipopolysaccharide-stimulated TNF-[alpha] and an increased IL-10 response. Coadministration of norepinephrine and IL-10 had synergistic effects. Although pretreatment with an anti-IL-10 antibody and labetalol before addition of plasma obtained at T2 largely restored the TNF-[alpha] response in vitro, their addition post-treatment failed to restore the monocytic TNF-[alpha] response.     

Effect of Intravenous Anesthetics on Spontaneous and Endotoxin-stimulated Cytokine Response in Cultured Human Whole Blood

Background: Various anesthetics have been suggested to interfere with the immune system. The ability of leukocytes to express surface receptors and mediators is fundamental to a successful host defense. Therefore, the effects of intravenous anesthetics on cytokine release by leukocytes and expression of surface molecules known to modulate this response were determined.

Methods: Concentration-dependent effects of thiopentone, etomidate, propofol, ketamine, midazolam, and fentanyl on spontaneous and endotoxin (lipopolysaccharide; 1 [micro sign]g/ml)-stimulated cytokine release were studied in whole blood from volunteers (n = 6) cultured for 25 h. In addition, expression of the lipopolysaccharide-recognition molecule CD14 and the major histocompatibility complex class II molecule human leukocyte locus A system-DR (HLA-DR) on monocytes were assessed using flow cytometry.

Results: All anesthetics studied elicited only minor effects on spontaneous cytokine release even at pharmacologic concentrations. However, expression density of CD14 was reduced in the presence of thiopentone, etomidate, and propofol, whereas HLA-DR was unaffected. lipopolysaccharide-stimulated tumor necrosis factor response was inhibited by thiopentone (12.8% [median]; 7.6-18.8 [25-75 percentile]) of control, and ketamine (46.4% [median]; 44.4-56.4 [25-75 percentile]), at pharmacologic concentrations, whereas it was augmented even in the presence of low concentrations of propofol (172.3% [median]; 120.5-200.7 [25-75 percentile]). Ketamine additionally decreased the concentration of interleukin (IL)-1 [small beta, Greek] (14.8% [median]; 12.0-18.0 [25-75 percentile]). Release of IL-1 receptor antagonist (IL-1ra) was inhibited by thiopentone, etomidate, and propofol, whereas the same anesthetics increased IL-10 concentration simultaneously. Midazolam and fentanyl did not alter the concentrations of any cytokine.     

Extravasation of albumin after cardiopulmonary bypass in newborns

OBJECTIVE: The systemic inflammatory response to cardiopulmonary bypass (CPB) possibly increases microvascular permeability to plasma proteins, leading to capillary leak syndrome. The study was conducted to elucidate any protein leakage in newborns using Evans blue dye as tracer. DESIGN: Prospective controlled study. SETTING: University-affiliated heart center. PARTICIPANTS: Eleven neonates with transposition of the great arteries. INTERVENTIONS: Plasma interleukin-6 (IL-6), IL-10, fractional escape rate (FER) of an intravenous bolus of Evans blue, and colloid osmotic pressure (COP) were assessed before and after surgery (statistics: median and 25th-75th percentile, Friedman's 2-way analysis of variance, and Wilcoxon matched-pairs signed-rank test [before and after surgery]). MEASUREMENTS AND MAIN RESULTS: All patients had an uneventful intraoperative course. The demographic and operative data were age 11 (10-13) days, body weight 3.2 (3.0-3.3) kg, CPB time 132 (123-144) minutes, and aortic cross-clamp time 66 (64-78) minutes. The proinflammatory IL-6 increased 60-fold and the anti-inflammatory IL-10 only 3-fold after CPB. FER, however, was not changed, whereas COP was significantly reduced after CPB. CONCLUSIONS: In contrast to the expectation, the escape rate of Evans blue, reflecting the extravasation of albumin, was not increased after CPB. However, reduced COP, hypothermia, and also a reduced lymphatic drainage may contribute to edema formation. The present data do not support the hypothesis of a capillary leak after CPB in newborns.     

Evidence for interleukin-1 beta production by cultured normal human osteoblast-like cells.

To determine if bone cells produce interleukin-1 beta (IL-1 beta), a potent bone resorption-stimulating agent, we studied well-characterized, nearly homogeneous cultures of normal human osteoblast-like (hOB) cells. With four strains of such cells, vehicle-treated cultures produced minimal IL-1 beta (mean +/- SEM, 1.3 +/- 0.3 pg/ml per 10(6) cells per 24 h) and showed dose-dependent (r = 0.99) increases to 2.2 +/- 0.7, 5.0 +/- 0.9, or 17.8 +/- 6.7 pg/ml, respectively, after treatment with lipopolysaccharide (LPS) at 3, 10, or 30 micrograms/ml (for increases after 10 and 30 micrograms/ml treatments, P less than 0.05). After treatment with tumor necrosis factor alpha (TNF-alpha) at 10 U/ml, IL-1 beta increased to 16.2 +/- 3.7 pg/ml (P less than 0.05). Neither 17 beta-estradiol nor bovine parathyroid hormone(1-34) (each at 10 nM), alone or in combination with LPS or TNF-alpha, affected IL-1 beta release. Northern blot analysis of total cellular RNA preparation revealed a single hybridization band at 1.9 kb when probed with a partially deleted cDNA for human IL-1 beta. The steady-state IL-1 beta mRNA levels showed a significant increase with LPS treatment and a lesser increase with TNF-alpha treatment in hOB cells. Moreover, TNF-alpha produced an even greater increase in IL-1 mRNA in HOBIT cells, a well-differentiated clonal cell line derived from normal hOB cells transfected with the SV40 large T antigen. We conclude that human cells of the osteoblast lineage produce IL-1 beta in response to well-recognized stimuli for IL-1 release from responsive tissue.(ABSTRACT TRUNCATED AT 250 WORDS)     

Interleukin-1 beta and tumor necrosis factor-alpha release in normal and diseased human infrarenal aortas.

The presence of chronic inflammatory cells in the adventitia and media of abdominal aortic aneurysms and aortic occlusive disease suggest an immunologic response. The purpose of this study is to determine whether normal or diseased infrarenal aortas liberate the inflammatory cytokines tumor necrosis factor-alpha (TNF-alpha) and interleukin-1 beta (IL-1 beta). Twenty-six infrarenal aortic biopsies (5 aortic occlusive disease, 15 abdominal aortic aneurysms, and 6 cadaveric donors) were weighed, minced into small pieces, and incubated in media for 48 hours. Conditioned media was harvested at 48 hours and assayed for IL-1 beta or TNF-alpha with use of an ELISA assay. Comparison of groups was performed with a one-way analysis of variance. The constitutive IL-1 beta produced by abdominal aortic aneurysms was significantly different than that in cadaveric donors (908 +/- 194 pg/ml [SE] vs 100 +2- 30 pg/ml). There was no statistically significant difference between abdominal aortic aneurysms and aortic occlusive disease (908 +/- 194 pg/ml vs 604 +/- 256 pg/ml) or aortic occlusive disease and cadaveric donor (604 +/- 256 vs 100 +/- 30). In time-course studies for the release of IL-1 beta, abdominal aortic aneurysms demonstrated maximal release at 48 hours. IL-1 beta release was augmented by lipopolysaccharide in all categories. A dose response curve demonstrated maximal IL-1 beta release on stimulation with 5 micrograms/ml LPS. Constitutive TNF-alpha production was low, ranging from 13 +/- 1.5 pg/ml in cadaveric donor, to 20 pg/ml in aortic occlusive disease, and 24 +/- 11 pg/ml in abdominal aortic aneurysms. There was no augmentation in TNF-alpha with lipopolysaccharide.(ABSTRACT TRUNCATED AT 250 WORDS)     

Withdrawal of therapy in patients with proliferative lupus nephritis: long-term follow-up.

BACKGROUND: Whether corticosteroid and immunosuppressive therapy may be safely withdrawn in patients with proliferative lupus nephritis is still unclear. METHODS: In 32 patients with biopsy-proven proliferative lupus nephritis previously put into remission, therapy was gradually tapered off. RESULTS: When immunosuppressive therapy was stopped (median: 38 months; 25th-75th percentile: 24-81 months, after biopsy), 24 patients were in complete remission and eight had a median proteinuria of 1.05 g/24 h (25th-75th percentile: 0.91-1.1 g/24 h) with normal renal function. After stopping therapy, patients were followed for a median of 203 months (25th-75th percentile: 116-230 months). Fifteen patients (Group 1) never developed lupus activity. The other 17 patients (Group 2) developed lupus exacerbations in a median of 34 months (25th-75th percentile: 29-52 months) after stopping therapy and were re-treated. The only significant differences between the two groups were the longer median durations of treatment, 57 months (25th-75th percentile: 41.5-113.5 months) vs 30 months (25th-75th percentile: 18-41 months; P<0.009), and remission, 24 months (25th-75th percentile: 18-41) vs 12 months (25th-75th percentile: 7-20 months; P<0.02), before stopping therapy in Group 1 than in Group 2. At last follow-up, 12 patients of Group 1 were in complete remission, two had mild proteinuria and one had died. In Group 2, one patient died, 14 were in complete remission, one had mild proteinuria and in another patient serum creatinine doubled. CONCLUSIONS: Some patients with severe lupus nephritis who enter stable remission can be maintained without any specific treatment for many years. Those patients who have new flares can again go into remission with an appropriate treatment. The longer the treatment and remission before withdrawal, the lower the risk of relapse.     

冠心病患者围手术期炎症反应的研究

目的　探讨体外循环或非体外循环下冠状动脉搭桥和激光心肌打孔治疗冠心病时围手术期炎症因子变化的特点 ,为冠心病围手术期的临床治疗提供参考。　方法　测定 37例冠心病患者及 10例瓣膜病患者术前 ,搭桥或打孔前 ,主动脉开放时 (搭桥结束时或打孔后 )及术后 3、6、2 4h的血浆肿瘤坏死因子 (TNF α)、白介素 6 (IL 6 )、C反应蛋白 (CRP)的水平。　结果　术后患者血浆TNF α、IL 6、CRP水平均有一定程度升高 ,使用体外循环患者TNF α为 (4 10± 0 71)pg/ml,显著高于不使用者的 (1 34± 0 2 9)pg/ml,差异有显著性意义 (P <0 0 5 ) ;两者IL 6差异无显著性意义 (P >0 0 5 )。冠状动脉搭桥患者术后CRP为 (12 89± 0 2 9) μg/ml,高于瓣膜病患者的 (12 0± 0 31) μg/ml,差异有显著性意义 (P <0 0 5 )。　结论　冠心病患者 ,冠状动脉搭桥、激光打孔手术后 ,围手术期均有一定程度的炎症反应 ,体外循环者反应较重     

Perioperative serum interleukins in neonates with hypoplastic left-heart syndrome and transposition of the great arteries

OBJECTIVE: The primary study objective was to examine the impact of diagnosis on the inflammatory response in neonates with congenital heart disease undergoing cardiac surgery. The secondary objective was to study the impact of the inflammatory response on postoperative outcome in these neonates. DESIGN: Observational study. SETTING: Tertiary care children's hospital heart center. PATIENTS: Neonates with hypoplastic left-heart syndrome (HLHS) undergoing stage I repair and patients with transposition of the great arteries (TGA) undergoing arterial switch operation. MEASUREMENTS AND MAIN RESULTS: There were 24 neonates with HLHS and 21 neonates with TGA. Serum samples to measure interleukin (IL)-6 and -10 were obtained before and after CPB at 1, 3, 6, and 24 hours postoperatively. Time to extubation, intensive care unit (ICU) length of stay, and peritoneal fluid drainage were compared between the groups. Serum IL-6 and IL-10 concentrations increased after CPB when compared to the preoperative concentration. Preoperative concentrations of IL-6 were significantly elevated in the HLHS group (HLHS: 32 [21.1, 69.6] pg/mL v TGA: 7.2 [3.6, 22.5] pg/mL [median, 25th, and 75th percentile], p = 0.003) and remained elevated immediately after CPB, and at 3 and 6 hours postoperatively. The IL-10 to IL-6 ratio was lower in the HLHS group preoperatively and immediately after CPB. ICU length of stay was significantly longer in the HLHS group (TGA 4 [3-6] days v HLHS 6 [5-8] days, p = 0.031). Mortality in the HLHS group (4/24) was associated with significantly higher IL-6 postoperatively (IL-6 immediately postoperatively: HLHS survivors 59.9 [34.3, 65.7] pg/mL v nonsurvivors 98.7 [94.4, 104.5] pg/mL, p < 0.011). CONCLUSIONS: All neonates with TGA or HLHS have a significant inflammatory response after CPB. Neonates with HLHS have evidence of an activated inflammatory response before CPB, which remains significant in the postoperative period. Accelerated interleukin expression and an abnormal cytokine balance correlate with longer time to extubation, longer ICU length of stay, and increased peritoneal fluid volume.     

Comparison of the inflammatory response between miniaturized and standard CPB circuits in aortic valve surgery.

OBJECTIVE: One of the complications of CPB is the systemic inflammatory response syndrome (SIRS). Recent developments tend to minimize the biological impact of CPB in using miniaturized closed circuit with reduced priming volume and less blood-air interface. The benefit of these miniaturized closed circuits in terms of inflammatory response has been proved in coronary surgery. However, in open heart surgery, the CPB circuit is no more closed and the benefit of the miniaturized set-up could disappear. The aim of the study is to compare the SIRS between standard and miniaturized circuits in aortic surgery. METHODS: Forty patients who underwent singular aortic valve replacement were randomly assigned either to a standard CPB (group A, n=20) or to a miniaturized CPB (group B, n=20). Pertinent clinical and surgical data were collected. Hematological parameters (leukocyte and neutrophil counts) and biochemical parameters (C-reactive protein, cytokine tests) were determined pre-, on and post-CPB. RESULTS: There were an increase in leukocyte and neutrophil counts and a decline in hematocrit in both groups. In both groups, there was a raise after CPB, in C-reactive protein, IL-6, TNF-alpha, neutrophil elastase, and IL-10. However, the raises of elastase and TNF-alpha were significantly lower after the weaning of miniaturized CPB (116+/-46 ng/ml and 10+/-4 pg/ml, respectively) compared to standard CPB (265+/-120 ng/ml, P=0.01 and 18+/-7 pg/ml, P=0.03). The raise of IL-10 is also lower with miniaturized circuit (15+/-6 pg/ml) compared to standard circuit (51+/-26, P=0.004). CONCLUSIONS: This study demonstrates in aortic surgery, the lesser inflammatory response of a miniaturized CPB compared to a standard CPB. However, there is always some inflammation after CPB and a small bio-reactive free perfusion circuit is still to be found in open heart surgery.     

Cardiac interleukin-6 release and myocardial recovery after aortic crossclamping. Crystalloid versus blood cardioplegia

BACKGROUND: Pro-inflammatory cytokines may play an important role in patient response to cardiopulmonary bypass (CPB). Since the myocardium is proposed to be a major source of cytokines, we studied the influence of the cardiolpegia type on interleukin-6 release and early myocardial recovery. METHODS: Experimental design: prospective, randomized study. Setting: university hospital, operative and intensive care. Patients: 20 consecutive patients (3 females) scheduled for elective coronary artery bypass grafting (CABG), mean age 62.8+/-5 years, history of myocardial infarction 11/20, left ventricular ejection fraction 62.9+/-15%. Interventions: patients were operated on using randomly either cold blood cardioplegia (B, n = 10) or cold crystalloid cardioplegia (C, n = 10). Measures: plasma levels of interleukin-6 (IL-6) were measured prior to CPB, after aortic declamping, after CPB, 1 hour, 6 hours and 12 hours postoperatively. RESULTS: Groups were comparable with respect to demographic data, left ventricular function, number of grafts, CPB and aortic crossclamp time. Group B patients demonstrated significant lower IL-6 levels after 1 hour (210+/-108 vs. 578+/-443 pg/ml), 6 hours (204+/-91 vs. 1210+/-671 pg/ml) and 12 hours (174+/-97 vs. 971+/-623 pg/ml). Post-CPB cardiac index was superior in group B (3.9+/-0.3 vs. 3.2+/-0.3 l/min/m2, p<0.05) with similar doses of inotropes. Group B patients could earlier be weaned off respirator (10+/-4 vs. 13+/-4 hours, p<0.05) and showed minor blood loss (635+/-211 vs. 918+/-347 ml, p<0.05). CONCLUSIONS: Inflammatory response to CPB is associated with delayed myocardial recovery. The use of blood cardioplegia may attenuate inflammatory reactions.     

Differential regulation of monocyte/macrophage cytokine production by pressure

BACKGROUND: Cytokine production by macrophages is essential for the inflammatory response. Normal human interstitial tissue pressure is 20 to 30 mm Hg, but generally decreases in acute inflammation. METHODS: We compared the effect of 20 mm Hg increased pressure (approximating normal interstitial tissue pressure) with that of ambient pressure (resembling pressure in inflamed tissues) on tumor necrosis factor (TNF)-alpha and interleukin (IL)-1beta production by undifferentiated (monocytic) and PMA (phorbol 12-, myristate 13-acetate)-differentiated (macrophage-like) THP-1 cells with or without lipopolysaccharide (LPS) (10 ng/mL). RESULTS: Pressure stimulated spontaneous macrophage TNF-alpha secretion (30.5 +/- 6.3 vs. 49.1 +/- 2.8 pg/mL, P <.02), but not monocyte TNF-alpha secretion. Pressure did not stimulate IL-1beta release. As expected, LPS increased basal cytokine release. After LPS stimulation, pressure still tended to stimulate macrophage TNF-alpha, but inhibited monocyte TNF-alpha secretion (P <.05). In contrast, pressure inhibited IL-1beta release by both LPS-treated monocytes (986 +/- 134 vs. 595 +/- 226 pg/mL, P <.02) and macrophages (3,112 +/- 229 vs. 979 +/- 61 pg/mL, P <.01). CONCLUSIONS: Extracellular pressure may regulate TNF-alpha and IL-1beta secretion differentially by monocytes and macrophages.     

Comparative effectiveness of methylprednisolone and zero-balance ultrafiltration on inflammatory response after pediatric cardiopulmonary bypass

Studies have demonstrated that systemic inflammatory response syndrome (SIRS) remains one of the major causes of cardiopulmonary bypass (CPB)-associated organ injury during pediatric cardiac surgery. The purpose of this investigation was to compare the effectiveness of methylprednisolone (MP) and zero-balance ultrafiltration (ZBUF) on SIRS during pediatric CPB. Thirty infants undergoing open-heart surgeries were randomized to receive either MP in the priming solution (group M, n = 15) or ZBUF during CPB (group Z, n = 15). All the patients survived. Plasma levels of tumor necrosis factor-alpha (TNF-alpha), interleukin-6 (IL-6), interleukin-8 (IL-8), and interleukin-10 (IL-10) were measured before CPB (T1), 5 min after the start of CPB (T2), at the termination of CPB (T3), the fourth hour (T4), and the eighth hour (T5) postoperatively. The results showed that the plasma concentrations of TNF-alpha in the Z group were significantly less than those in the M group at T4 and T5 (P < 0.05), and the plasma concentrations of IL-6 were significantly less than those in the M group at T4 (P < 0.05); the plasma concentrations of IL-8 in the Z group were significantly less than those in the M group at T5 (P < 0.05). There was no difference between two groups on the plasma concentrations of IL-10. The duration of postoperative mechanical ventilation was (9.6 +/- 0.8 h) in the M group and (7.8 +/- 0.4 h) in the Z group (P < 0.05). This study showed that application of ZBUF is more effective to decrease the level of inflammatory mediators including TNF-alpha, IL-6, and IL-8 than administration of MP after pediatric CPB.     

Elevated plasma concentration of IP-10 in patients with type 2 diabetes mellitus

Recent studies have shown the important role of proinflammatory cytokines and chemokines in the pathogenesis of atherosclerosis and diabetes mellitus(DM). Interferon-inducible protein of 10 kD (IP-10/ CXCL10), a member of the C-X-C chemokine superfamily, is a potent chemoattractant for activated T lymphocytes and is reported to be involved in various disease states including atheroma plaque formation, inhibition of tumor angiogenesis and maintenance of podocyte function. However, the involvement of IP-10 in type 2 DM, especially in its vascular and renal complications, is largely unknown. To elucidate the etiopathological role of IP-10 in type 2 DM, we measured the concentrations of IP-10 together with IFN-gamma, TNF-alpha, IL-18, IL-6 and MCP-1 in plasma samples from 103 type 2 DM patients with various degrees of nephropathy. A significant difference in the plasma level of IP-10 was observed between the patients and the control subjects (183.3+/-12.5 pg/m/ vs 65.6+/-9.3 pg/ml, p<0.05). IP-10 correlated IL-18, IL-6, TNF-alpha and MCP-1. The IFN-gamma level was below the detectable range. IP-10 levels became higher with the progression of nephropathy : IP-10 levels were 148.9+/-14.5, 174.2+/-17.2 and 231.9+/-31.3 pg/m/ in patients with an urinary albumin creatinine ratio of <30, 30 to 300 and >300 microg/mg Cr, respectively. Similarly, IL-18, IL-6, MCP-1 and TNF-alpha levels in patients with overt albuminuria were significantly higher as compared with those without albuminuria (IL-18, 367.3 45.6 vs 203.5+/-17.6 pg/ml; IL-6, 1.61+/-0.26 vs 0.87+/-0.13 pg/ml; TNF-alpha, 1.83+/-0.48 vs 0.61+/-0.07 pg/ml; p<0.05, respectively) in consistent with previous reports. These results suggested that IP-10 may have an etiopathogenic role in type2 DM and diabetic nephropathy as one of the downstream effectors of proinflammatory cytokines.     

Systemic inflammatory response in acute cholangitis and after subsequent treatment.

OBJECTIVE: To measure the concentrations of endotoxin and inflammatory mediators during an attack of acute cholangitis and see what effect endoscopic treatment had on these mediators. DESIGN: Prospective study. SETTING: University teaching hospital The Netherlands. SUBJECTS: Ten patients with acute cholangitis. INTERVENTIONS: Measurements were made during the attack and 1 week after endoscopic treatment. MAIN OUTCOME MEASURE: Changes in clinical variables, and severity of biliary obstruction. Concentrations of endotoxin, cytokines, and endotoxin binding proteins, in plasma. RESULTS: The causes of cholangitis were obstructed endoprosthesis (n = 4) and stones (n = 6). The median bilirubin concentration during the attack was 70.0 micromol/L (range 14-156) and 14.5 micromol/L (range 9-80) after treatment (p < 0.05). Median (range) plasma endotoxin concentrations were 3.6 pg/ml (3.2-107) and 3.6 (2.4-5), respectively. Concentrations of cytokines were high during the acute attack and significantly lower after treatment: median tumour necrosis factor (TNF) fell from 44.6 pg/ml (range 1.2-403) to 7.3 (0-53); soluble TNF receptor p55 from 4.9 ng/ml (2.7-13.8) to 3.6 (1.4-8.2) and TNF receptor p75 from 11.6 ng/ml (7.1-40.6) to 8.1 (2.9-31.3); interleukin 6 (IL-6) fell from 690 pg/ml (34.1-4594) to 8.2 (0-39.3), IL-8 from 226.2 pg/ml (31.6-712.7) to 21.4 (4.2-63.5) and IL-10 from 33.4 pg/ml (2.7-5605) to 4.7 (0-16.7) (p < 0.03). Values for lipopolysaccharide binding protein and soluble CD14 also fell significantly (p < 0.01) from 86.5 (43.4-200) to 21.5 (11.3-37.5) and from 200 (59-200) to 47.8 (0.47-200), respectively. The concentration of bactericidal permeability increasing protein did not change significantly, being 7.1 (2-18.9) during the acute attack and 4.6 (0.8-17.7) a week later. CONCLUSION: There is a considerable systemic inflammatory response during cholangitis, which is dramatically reduced one week after endoscopic treatment.     

In vitro restoration of post-operatively decreased IFN-gamma levels after cardiac surgery and its effect on pro- and anti-inflammatory mediators

BACKGROUNDS: A decreased synthesis of interferon gamma (IFN-gamma) by TH 1 lymphocytes after cardiac operations with cardiopulmonary bypass (CPB) is part of the inflammatory response to local operative and systemic traumas. The consequences of this mechanism on the release of pro- and anti-inflammatory cytokines remain unclear. To evaluate the role of IFN-gamma, we added recombinant IFN-gamma to peripheral blood mononuclear cells (PBMCs) on the first post-operative day in an attempt to restore pre-operative values and then measured the release of pro- and anti-inflammatory cytokines in vitro. METHODS: PBMCs of 10 patients scheduled for elective coronary artery bypass grafting (CABG) were obtained pre-operatively (d0) and on the first (d1) and third (d3) post-operative days. The release of IL-6, IL-8, TNF-alpha, IFN-gamma, IL-10, IL-2, and IL-4 was studied after stimulation (48 h) with PHA (phytohemagglutinin) and LPS (lipopolysaccharide) in the absence or presence of recombinant human IFN-gamma. RESULTS: Endogenous IFN-gamma synthesis was suppressed on d1. Adding exogenous IFN-gamma restored IFN-gamma levels to normal on d1 and doubled IFN-gamma levels on d0 and d3. The addition of IFN-gamma increased TNF-alpha levels up to 250% on d1 and IL-2 synthesis by 75% on d1 and d3; the IL-2 levels, however, were still significantly depressed. The addition of recombinant IFN-gamma did not affect the synthesis of IL-6, IL-8, IL-10, and IL-4. CONCLUSIONS: Contrary to our expectations, the in vitro release of IL-6 and IL-8 as well as IL-10 and IL-4 was not influenced by the addition of IFN-gamma. However, TNF-alpha production in isolated PBMC cultures increased significantly on the first post-operative day. This may indicate a hyper-reactivity of PBMCs to IFN-gamma and suggests that the decrease in IFN-gamma synthesis might prevent an excessive stimulation of the non-specific immune system by high TNF-alpha levels after cardiac surgery.     

Highly efficient ex vivo gene transfer to the transplanted heart by means of hypothermic perfusion with a low dose of adenoviral vector

BACKGROUND: Hypothermic conditions required for donor heart preservation may reduce gene-transfer efficiency. Experiments were designed to determine whether a perfusion technique could improve the efficiency of gene transfer to donor hearts. METHODS: An adenoviral vector encoding beta-galactosidase (3.5 x 10(8) plaque-forming units) was infused into explanted rat hearts under 4 conditions (each n = 6): (1) the virus was diluted in 350 microL of University of Wisconsin solution and infused as a high-pressure bolus into the coronary arteries of donor hearts through the aortic root; (2) the virus was diluted in 5 mL of University of Wisconsin solution and circulated by means of a peristaltic pump (flow, 0.75 mL/min) through the vasculature of the donor heart for 30 minutes; (3) 5 mL of viral solution was circulated as for group 2 for 15 minutes; and (4) 5 mL of viral solution was circulated for 5 minutes at a flow rate of 2.4 mL/min. Transduced hearts were transplanted into the abdomen of syngeneic rats, and transgene expression was assessed by means of immunoassay 4 days later. RESULTS: The median beta-galactosidase content was (1) 45.0 ng/mg protein (25th-75th percentile, 33-73 ng/mg), (2) 640 ng/mg protein (25th-75th percentile, 614-878 ng/mg), (3) 493.8 ng/mg protein (25th-75th percentile, 456-527 ng/mg), and (4) 503.3 ng/mg protein (25th-75th percentile, 475-562 ng/mg; P <.01 for group 2 vs group 1, and P <.05 for groups 3 and 4 vs group 1). Transgene expression was predominantly in myocytes and favored the subepicardial region of the right ventricle. CONCLUSION: Hypothermic perfusion of the donor heart with an adenoviral vector resulted in efficient transgene expression compared with that induced by a single bolus injection.     

Long-term durability of resection and end-to-end anastomosis for ascending aortic aneurysms

BACKGROUND: Ascending aortic aneurysms with normal sized sinotubular junction are generally treated by resection of the dilated aorta and replacement with tubular graft. Aortic resection and direct end-to-end anastomosis has been applied to repair aortic coarctation, interrupted aortic arch, and traumatic aortic rupture. No data exist regarding the long-term durability of this approach in ascending aortic aneurysms. The aim of this case-control study was to illustrate the durability of this operation by presenting our entire experience and the long-term follow up of a cohort of 34 patients who underwent ascending aortic aneurysm resection and primary end-to-end anastomosis between January 1990 and March 2003 in Caen University Hospital (Caen, France). METHODS: The mean age of patients was 61.5 +/- 12.5 years, and there were 18 male and 16 female patients. The operative technique included extensive mobilization of the arch, supra-aortic trunks, and inferior vena cava to enable approximation of the aortic ends, thus avoiding tension on the suture lines. Associated aortic valve replacement was performed in 27 patients; mechanical valves were used in 19. A bicuspid aortic valve was present in 9 patients; in 3 cases the valve was regurgitant. Aortic valve regurgitation was present in a total of 7 patients. Patients were followed up at regular intervals; total follow-up was 2187 patient-months, with a median follow-up time of 72 months per patient (25th-75th percentile 10.5-102.7 months). RESULTS: One patient died 10 days after the operation of aortic rupture related to suture infection caused by mediastinitis. Late deaths occurred in 3 patients, who died 12, 62, and 71 months after the operation, but none of these deaths were attributable to late aortic repair failure. No patient in this series required reoperation, including patients with aortic regurgitation or bicuspid aortic valve. Follow-up was 91.1% complete at the closing date of April 1, 2003. The Kaplan-Meier estimate of survival for all patients was 120.4 months (95% confidence interval 105.1-135.7 months). The median of preoperative maximal aortic diameter was 55.1 mm (range 50.3 to 67.5 mm, 25th-75th percentile 50.5-56.8 mm). The median immediate postoperative diameter was 40.3 mm (range 33.4-46.4 mm, 25th-75th percentile 37.2-42.0 mm, P <.0001 relative to preoperative diameter), and the median length of the resected aortic segment was 52 mm (range 48-76 mm, 25th-75th percentile 50.1-66.4 mm). The median decrease of aortic diameter was 24.9 mm (range 8.9-32.6 mm, 25th-75th percentile 18.2-26.6 mm).The median aortic diameter at the end of the follow-up was 41.0 mm (range 34.6-46.1 mm, 25th-75th percentile 37.0-43.2 mm, P =.6 relative to immediate postoperative diameter). CONCLUSIONS: Ascending aorta aneurysm resection and primary end-to-end anastomosis provides effective long-term outcome and in selected cases represents a good alternative to aortic interposition grafting. Aortic regurgitation and bicuspid aortic valve do not represent a contraindication for this treatment.     

IL-8, IL-6 and ICAM-1 in serum of paediatric patients undergoing cardiopulmonary bypass with and without cardiocirculatory arrest

BACKGROUND: The aim of the present study was to evaluate the systemic inflammatory response to CPB in paediatric patients undergoing surgical correction of congenital heart diseases. METHODS: Experimental design: comparative investigation. Setting: paediatric cardiology hospital Intervention: ICAM-1, IL-8, and IL-6 production were analysed before and during CPB, and after surgery in 9 paediatric patients, submitted to cardiocirculatory arrest (Group A); and in 11 without cardiocirculatory arrest (Group B). Measures: ICAM-1, IL-8, and IL-6 production were analysed from arterial samples before and during CPB, and after surgery. RESULTS: In group A vs group B a significant increase of IL-8 was detected during (297+/-250 vs 11+/-19 pg x ml(-1), p<0.001) and after (100+/-230 vs n.d. pg x ml(-1)) surgery and was correlated with the duration of operation (r=0.759; p=0.0001) and clamping time (r=0.738; p<0.05). After surgery in group A, IL-6 levels (35+/-43 pg x ml) were higher than those in group B (2+/-5 pg x ml), and a good correlation was observed between IL-6 and duration of aortic clamping (r=0.714; p=0.048), cardiac arrest, (r=0.714; p=0.048), and length of surgery (r=0.867; p=0.04). CONCLUSIONS: In children who underwent CPB with cardiocirculatory arrest cytokine production seems related to duration of operation and amplified by ischemia-reperfusion phenomena.     

Comparison of systemic cytokine levels in patients with acute respiratory distress syndrome, severe pneumonia, and controls

BACKGROUND: The inflammatory response has been widely investigated in patients with acute respiratory distress syndrome (ARDS) and pneumonia. Studies investigating the diagnostic values of serum cytokine levels have yielded conflicting results and only little information is available for the differential diagnosis between ARDS and pneumonia. METHODS: Clinical and physiological data, serum concentrations of tumour necrosis factor (TNF)-alpha, interleukin (IL)-1beta and IL-6, and quantitative cultures of lower respiratory tract specimens were obtained from 46 patients with ARDS and 20 with severe pneumonia within 24 hours of the onset of the disease and from 10 control subjects with no inflammatory lung disease. Cytokine concentrations were compared between groups and determinants in addition to the diagnosis were tested. RESULTS: Serum TNF-alpha levels were significantly higher in ARDS patients (67 (57) pg/ml) than in patients with severe pneumonia (35 (20) pg/ml; p = 0.031) or controls (17 (8) pg/ml; p = 0.007). For IL-1beta and IL-6 the observed differences were not statistically significant between patients with ARDS (IL-1beta: 34 (65) pg/ml; IL-6: 712 (1058) pg/ml), those with severe pneumonia (IL-1beta: 3 (4) pg/ml, p = 0.071; IL-6: 834 (1165) pg/ml, p = 1.0), and controls (IL-1beta: 6 (11) pg/ml, p = 0.359; IL-6: 94 (110) pg/ml, p = 0.262). TNF-alpha (standardised coefficient beta = 0.410, p<0.001) and IL-1beta (standardised coefficient beta = 0.311, p = 0.006) were most strongly associated with the degree of lung injury, even when the diagnostic group was included in the statistical model. CONCLUSIONS: Serum TNF-alpha levels were higher in patients with ARDS than in those with severe pneumonia or in control subjects. Multivariate results suggest that the levels of systemic TNF-alpha and IL-1beta reflect the severity of the lung injury rather than the diagnosis.