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H F Galley

Publications and source records attributed to H F Galley.

At least 19 recordsLinked to original sources
PubMed1999

T helper cell subset ratios in patients with severe sepsis.

BACKGROUND: T helper 1 (Thl) lymphocytes produce interferon gamma (IFNgamma), favouring cell mediated immunity; Th2 cells secrete interleukin-4 (IL-4), favouring humoral immunity. Cytokines produced in sepsis may effect Th subset predominance and subsequent immune responses. METHODS: We measured Th subsets in ten patients with severe sepsis, seven APACHE II score-matched non-septic critically ill control patients, and ten healthy subjects. Mononuclear leukocytes were isolated and Th subsets identified by flow cytometry. RESULTS: The median (range) Th1/Th2 ratio was 0.46 (0.2-2.5) in patients with sepsis, which was significantly lower than both non-septic controls (median 2.5 (0.2-5.9), p = 0.050) and healthy subjects (median 3.9 (1.2-10.8), p = 0.01). CONCLUSIONS: In patients with sepsis, Th2 antibody mediated (humoral) immune responses predominate. This type of response may lead to fibroblast activation and ultimately immunosuppression. Modulation of Th cell subset predominance may present a novel therapeutic option in the treatment of severe sepsis.

APACHE↗
PubMed1999

Acidosis and tissue hypoxia in the critically ill: how to measure it and what does it mean.

We routinely monitor blood gases to determine the adequacy of ventilation and the presence of acid-base abnormalities. Changes in the blood are easily assessed, but of more importance is the abnormality at tissue level. Defects in acid-base homoeostasis have major effects on protein function, thus affecting tissue and organ performance. We concentrate on the changes seen in critically ill patients with acidosis because they form a large portion of the workload of the average intensive care unit. In addition, such patients have significant morbidity and mortality. The development of acidemia in the critically ill is often attributed to reductions in oxygen utilization, which in the past has generally been regarded as dysregulation of tissue blood supply. Resulting tissue hypoperfusion leads to anaerobic metabolism and lactic acidosis. Carbon dioxide production increases as anaerobically produced hydrogen ions are buffered by extracellular bicarbonate. The effectiveness of tissue perfusion is the target of much research, and in this review we outline factors that affect tissue acid-base status, techniques to measure tissue acid-base status, and explore the relationship between tissue acidosis and hypoxia in the critically ill. However, things are not always as simple as they may first appear.

Acid-Base Equilibrium↗
PubMed1999

Effect of the nitric oxide inhibitor, L-N(G)-monomethylarginine, on accumulation of interleukin-6 and interleukin-8, and nuclear factor-kappaB activity in a human endothelial cell line.

OBJECTIVE: To determine the effect of the nitric oxide synthase inhibitor, L-N(G)-monomethylarginine, on interleukin-6 and interleukin-8 accumulation, and nuclear factor-kappaB expression in an endothelial cell model of sepsis. DESIGN: Controlled cell culture experiments examining the immunomodulatory effects of nitric oxide synthase inhibition. SUBJECTS: A human endothelial cell line (EA.hy926). MEASUREMENTS AND RESULTS: Cells were incubated with tumor necrosis factor-alpha and interleukin (IL)-1beta in the presence of L-N(G)-monomethylarginine (L-NMMA). IL-6 and IL-8 were measured in culture supernatants using enzyme immunoassay. Nuclear factor-kappaB was measured using electrophoretic mobility shift assay and was quantified using phosphorimaging. IL-6 accumulation was decreased (p < .05) and IL-8 accumulation increased (p < .01) with L-NMMA. Increased nuclear factor-kappaB expression in stimulated cells was unaltered on exposure to L-NMMA. Cell viability was unaffected. CONCLUSIONS: Excessive production of nitric oxide has been implicated in septic shock, and the use of nitric oxide synthase inhibitors has been suggested. The immunoregulatory actions of nitric oxide synthase inhibitors affects the profile of cytokine release. This effect is not mediated through modulation of nuclear factor-kappaB. These findings have implications for the use of nitric oxide synthase inhibiting agents in septic shock.

Cell Line↗
PubMed1998

The effect of nitric oxide and peroxynitrite on apoptosis in human polymorphonuclear leukocytes.

In acute lung injury, neutrophil apoptosis may be important in regulating the inflammatory process by controlling neutrophil numbers and thus activity. Exogenous inhaled nitric oxide is now a widely used therapy in patients with acute lung injury, and its effects on apoptosis may be important. We investigated the effect of nitric oxide and peroxynitrite on apoptosis in lipopolysaccharide stimulated polymorphonuclear leukocytes as a model of nitric oxide-treated lung injury. Cells were incubated for up to 16 h with and without 1.7 microg/ml lipopolysaccharide and the nitric oxide donor GEA-3162 or the peroxynitrite donor SIN-1. Apoptosis was assessed using flow cytometry following annexin-V staining, after 4, 6, 8, and 16 h. Data were assessed using Kruskal-Wallis analysis of variance or Mann-Whitney U-test as appropriate. Annexin-V staining increased spontaneously over 16 h in untreated cells (p = .0002) and incubation with either 1000 microM SIN-1 or 10 microM GEA-3162 increased annexin staining at early time points in nonactivated cells. Apoptosis was attenuated when cells were exposed to lipopolysaccharide and both nitric oxide and peroxynitrite dose dependently inhibited this suppression at all time points and was most apparent at 16 h (p = .004 and .001, respectively). Exposure of activated neutrophils to exogenous nitric oxide or peroxynitrite has marked influences on apoptosis. This work has implications for the modulation of neutrophil function within the lung in patients with lung injury who receive inhaled nitric oxide therapy.

Annexin A5↗
PubMed1998

The effects of nitric oxide and peroxynitrite on interleukin-8 and elastase from lipopolysaccharide-stimulated whole blood.

UNLABELLED: Inhaled nitric oxide is now widely used in the treatment of hypoxemia and pulmonary hypertension in critically ill patients. Interleukin-8 (IL-8) and neutrophil elastase are important markers of the onset and severity of acute lung injury. We studied the effects of nitric oxide and peroxynitrite on IL-8) and elastase accumulation in lipopolysaccharide-activated whole blood. The nitric oxide donor (GEA-3162) did not affect IL-8 accumulation (P = 0.195) but did cause an increase in elastase accumulation (P = 0.007). The peroxynitrite donor (SIN-1) caused an increase in both IL-8 accumulation (P = 0.0004) and elastase accumulation (P = 0.007). The lack of effect of nitric oxide could be explained by the scavenging of nitric oxide by hemoglobin. These results suggest that modulation of the inflammatory response may occur during inhaled nitric oxide therapy in the critically ill. IMPLICATIONS: Inhaled nitric oxide, used in lung injury, reacts within the lung, forming peroxynitrite. We investigated the effect of nitric oxide and peroxynitrite on interleukin-8 and elastase release by white cells during inflammation. Nitric oxide and peroxynitrite had marked effects on elastase and interleukin-8, which suggests modulation of the inflammatory response.

Free Radical Scavengers↗
PubMed1998

The effect of midazolam and propofol on interleukin-8 from human polymorphonuclear leukocytes.

UNLABELLED: Anesthetics and sedatives contribute to postoperative immunosuppression. Interleukin-8 (IL-8) is a chemotactic and activating factor that mediates neutrophil adhesion and margination and is essential for host defense. We investigated the effect of anesthetics on isolated human polymorphonuclear leukocyte production of IL-8. Healthy human polymorphonuclear leukocytes were isolated using a single-step density gradient and stimulated with lipopolysaccharide in the presence of varying concentrations of propofol or midazolam for up to 20 h. IL-8 was measured in both culture supernatants and cell lysates using enzyme immunoassay, and IL-8 mRNA in cells was measured using Northern blotting and phosphorimaging. Data were analyzed using Kruskal-Wallis analysis of variance or the Mann-Whitney U-test as appropriate. Lipopolysaccharide increased extracellular accumulation of interleukin-8, which was suppressed by both propofol (P = 0.025) and midazolam (P = 0.028). However, intracellular IL-8 increased with exposure to lipopolysaccharide (P = 0.028) and remained increased with both anesthetics. Northern blot analysis also revealed increased IL-8 mRNA levels in the presence of both midazolam and propofol, which was confirmed by molecular imaging. These data strongly suggest that the anesthetics modulate transport or secretion of IL-8 protein from the cell. Suppression of IL-8 by anesthetics and sedatives may predispose postoperative and intensive care patients to infection. IMPLICATIONS: Anesthesia causes immune suppression and alters neutrophil function. We investigated the effect of propofol and midazolam on interleukin-8, a neutrophil chemotactic agent in human neutrophils. Both anesthetics decreased extracellular interleukin-8 accumulation, but intracellular levels and mRNA remained high. This suggests that propofol and midazolam alter interleukin-8 secretion from cells.

Analysis of Variance↗
PubMed1998

Spinal but not general anesthesia increases the ratio of T helper 1 to T helper 2 cell subsets in patients undergoing transurethral resection of the prostate.

UNLABELLED: Surgical stress and anesthesia cause immunosuppression that may predispose patients to postoperative infections. T helper lymphocytes play a major role in the immune response by controlling cell-mediated and humoral immunity. The type of immune response generated is determined by the differentiation of precursor T helper cells into Th1 or Th2 cells. Each cell subset secretes a particular array of cytokines that further augment the differentiation into that subset. Th1 cells produce interferon gamma and are responsible for cell-mediated immunity. Th2 cells produce interleukin-4 and are more effective in inducing humoral immunity. Cytokine concentrations are altered during surgery and anesthesia, which may effect Th cell predominance and, therefore, subsequent immune responses. We determined Th1 to Th2 cell ratios in patients undergoing transurethral resection of the prostate (TURP) using either spinal or general anesthesia. Mononuclear cells were isolated before anesthesia, immediately after surgery, and after 24 h from patients undergoing TURP, 10 under general anesthesia and 9 under spinal anesthesia. T helper cell subsets were quantified by using flow cytometry, and the ratio of Th1 to Th2 cells was calculated. Th1 to Th2 ratios in patients receiving spinal anesthesia increased over the three time points studied (P = 0.029) but did not change in patients who had general anesthesia (P = 0.11). At 24 h, Th1 to Th2 ratios were significantly higher in the spinal group than in patients who received general anesthesia (P = 0.0157). Total T helper cell numbers remained constant. These data suggest that, from an immunological viewpoint, spinal anesthesia, but not general anesthesia, benefits the patient by maintaining Th1 cell numbers, thereby promoting cellular immunity. IMPLICATIONS: Spinal anesthesia may result in less immunosuppression after surgery. We found that the ratio of T helper 1 to T helper 2 cells was higher in patients undergoing prostate surgery by spinal rather than general anesthesia. Th1 cells promote protective immune responses that may result in fewer postoperative infections.

Aged↗
PubMed1998

Nitric oxide synthase activity is increased in relation to the severity of liver dysfunction.

1. Nitric oxide is a potent vasodilator which plays a major role in the control of blood pressure. The hyperdynamic circulation of cirrhosis has been linked to nitric oxide.2. We measured neutrophil nitric oxide synthase activity in relation to the level of hepatic dysfunction in patients with liver disease of varying aetiology and severity.3. Neutrophils were isolated from 21 patients (7 Child-Pugh score A, 6 grade B and 8 grade C) aged 28-76 (median 49) years. Nitric oxide synthase activity was measured using the conversion of oxyhaemoglobin to methaemoglobin by nitric oxide and expressed in terms of cell protein. Blood pressure and biochemical indices were recorded. Data were assessed using Kruskal-Wallis one-way analysis of variance, Mann-Whitney U-test or Pearson correlation as appropriate.4.Systolic, mean arterial and diastolic blood pressures decreased with increasing hepatic damage (P=0.031, P=0.01 and P=0. 038 respectively). Nitric oxide synthase activity increased with the degree of liver dysfunction (P=0.033) and was highest in patients with Child-Pugh score C. Systolic blood pressure correlated with nitric oxide synthase activity in patients with Child-Pugh score C (P=0.029).5. Our results show that nitric oxide synthase activity increases with increasing Child-Pugh score and is associated with the development of systemic hypotension. These data may support the involvement of nitric oxide in the haemodynamic disturbances seen in liver disease.

Adult↗
PubMed1997

The effects of intravenous antioxidants in patients with septic shock.

Oxidative stress is implicated in septic shock. We investigated the effect of intravenous antioxidant therapy on antioxidant status, lipid peroxidation, hemodynamics and nitrite in patients with septic shock. Thirty patients randomly received either antioxidants (n-acetylcysteine 150 mg/kg for 30 min then 20 mg/kg/h plus bolus doses of 1 g ascorbic acid and 400 mg alpha-tocopherol) or 5% dextrose. Basal vitamin C was low and redox-reactive iron was elevated in all patients. In the 16 patients receiving antioxidants, vitamin C increased (p = .0002) but total antioxidant capacity was unaffected. Lipid peroxides were elevated in all patients but did not increase further in the patients receiving antioxidants. Plasma total nitrite also increased (p = .007) in the antioxidant group. Heart rate increased in patients receiving antioxidants at 60 min (p = .018) and 120 min (p = .004). Cardiac index also increased at 60 min (p = .007) and 120 min (p = .05). Systemic vascular resistance index decreased at 120 min in the antioxidant treated patients (p = .003). The effect of antioxidants on hemodynamic variables has not previously been reported. Antioxidant administration may be a useful adjunct to conventional approaches in the management of septic shock.

Acetylcysteine↗
PubMed1997

Combination oral antioxidant supplementation reduces blood pressure.

1. Hypertension affects 30% of adults and low intakes of antioxidants have been associated with increased risk of hypertension and cardiovascular disease. To investigate the effect of short-term high-dose antioxidant supplementation on blood pressure in hypertensive and normotensive outpatients, we undertook a randomized, double-blind, crossover design placebo-controlled study. 2. Forty subjects were recruited from medical outpatient clinics, of whom 38 completed the study. Twenty-one were attending for treatment of hypertension and 17 were normotensive, attending for minor gastrointestinal complaints. Subjects were randomly assigned to receive either 8 weeks placebo followed by 2 weeks washout then 8 weeks antioxidants or vice versa. The combination of antioxidants consisted of 200 mg of zinc sulphate, 500 mg of ascorbic acid, 600 mg of alpha-tocopherol (sodium succinate salt) and 30 mg of beta-carotene daily. 3. Systolic blood pressure fell at the end of the antioxidant phase compared with the placebo phase both in subjects receiving anti-hypertensive therapy (P < 0.01) and those who were normotensive (P = 0.067). Circulating levels of beta-carotene and alpha-tocopherol increased in all subjects during supplementation (P < 0.01) and urine nitrite increased in hypertensive patients (P < 0.05). 4. Short-term oral high-dose combination antioxidant therapy reduces blood pressure, possibly via increased availability of nitric oxide. This study may have implications for the innovative use of antioxidants as an adjunct to anti-hypertensive therapy.

Administration, Oral↗
PubMed1997

Flow cytometry.

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Anesthetics, Intravenous↗
PubMed1997

Effect of exogenous nitric oxide and superoxide on interleukin-8 from human polymorphonuclear leucocytes.

Patients with acute inflammatory lung injury are commonly treated with inhaled nitric oxide. Nitric oxide has profound immunoregulatory effects. Increased concentrations of the cytokine interleukin-8 (IL-8) in bronchoalveolar lavage fluid has been associated with disease severity. We have investigated the effects of a nitric oxide donor and a combined nitric oxide-superoxide donor on lipopolysaccharide-mediated accumulation of IL-8 from cultured human neutrophils. Interleukin-8 was measured in culture supernatant after 20 h using enzyme immunoassay. The combined nitric oxide-superoxide donor, 3-morpholinosydnonimine (SIN-1), dose-dependently decreased lipopolysaccharide-mediated IL-8 accumulation (P < 0.01). SIN-1 also decreased IL-8 accumulation from unstimulated neutrophils (P < 0.001). In contrast, the pure nitric oxide donor, 1,2,3,4-oxatriazolium 5-amino chloride (GEA-3162), increased stimulated IL-8 accumulation (P < 0.01) and also increased IL-8 accumulation in unstimulated cells (P < 0.002). Nitric oxide and superoxide have profound effects on IL-8. These results have important implications for the treatment of patients with acute lung injury with inhaled nitric oxide.

Cell Culture Techniques↗
PubMed1997

Changes in inflammatory mediators during orthotopic liver transplantation.

Transplantation is associated with an inflammatory rejection response. Graft reperfusion causes typical haemodynamic and biochemical responses. In this study we have investigated the relationship between these haemodynamic responses and changes in circulating inflammatory mediators after graft reperfusion in 10 consecutive patients undergoing orthotopic liver transplantation. After reperfusion, systemic vascular resistance index decreased (P = 0.011) and cardiac index increased (P = 0.038). These characteristic haemodynamic changes of the reperfusion syndrome were accompanied by global increases in cytokine concentrations. Plasma concentrations of leukotrienes decreased, while thromboxane B2 and platelet activating factor remained increased throughout. Reperfusion-mediated changes in inflammatory mediators may account for the haemodynamic disturbance.

Adult↗
PubMed1997

Effect of ciprofloxacin on the accumulation of interleukin-6, interleukin-8, and nitrite from a human endothelial cell model of sepsis.

OBJECTIVE: To determine the effect of the quinolone antibiotic ciprofloxacin, on interleukin-6, interleukin-8, and nitrite production by human endothelial cells. DESIGN: Controlled cell culture experiments examining the immunomodulatory effects of an antibiotic. SETTING: University research laboratory attached to a large teaching hospital. SUBJECTS: A human endothelial cell line. MEASUREMENTS AND MAIN RESULTS: Cells were incubated with tumor necrosis factor-alpha and interleukin-1beta in the presence of a range of ciprofloxacin concentrations. Interleukin-6, interleukin-8, and nitrite concentrations were measured in culture supernatants after 24 hrs using enzyme immunoassay. Ciprofloxacin decreased interleukin-6 accumulation (p = .001). Interleukin-8 was decreased at lower ciprofloxacin concentrations (p = .017) but was increased at 100 microg/mL (p = .0039). Ciprofloxacin had no effect on nitrite accumulation (p = .38). CONCLUSIONS: Ciprofloxacin differentially modulates interleukin-6 and interleukin-8 expression. The response to infection is coordinated by a cascade of cytokines and other mediators. The widespread use of ciprofloxacin in patients with severe infections is likely to result in alterations in local concentrations of cytokines. Selective control of cytokine concentrations by antibacterial agents will clearly have important therapeutic implications and may be a future research consideration in antibiotic drug design.

Anti-Infective Agents↗
PubMed1996

Elevated serum bleomycin-detectable iron concentrations in patients with sepsis syndrome.

OBJECTIVE: To determine serum bleomycin-detectable ¿free' iron in patients with septic shock and to relate these findings to both outcome and a marker of free radical damage. DESIGN: A prospective observational study. SETTING: A nine-bed intensive care unit in a university teaching hospital. PATIENTS: Sixteen consecutive patients with septic shock, defined as: (1) Clinical evidence of acute infection; (2) hypo- or hyperthermia ( < 35.6 degrees or > 38.3 degrees C); (3) tachypnoea ( > 20 breaths/min or ventilated); (4) tachycardia ( > 90 beats min); (5) shock (systolic pressure < 90mmHg) or on inotropes. Fourteen patients also had secondary organ dysfunction. MEASUREMENTS AND RESULTS: Bleomycin-detectable iron concentrations were elevated in all patients (37.2 +/- 11.0 mumols/l vs 5.1 +/- 3.3 mumols/l in healthy subjects, P < 0.0001), but there was no difference between patients who died and those who survived (39.2 +/- 9.3 and 36.2 +/- 12.3 mumols/l, respectively). Thiobarbituric acid reactive substances (an index of lipid peroxidation) were higher in those who died (3.33 +/- 2.29 mumols/l) than in the surviving patients (0.99 +/- 0.14 mumols/l, P < 0.01) or healthy subjects (0.92 +/- 0.39 mumols/l, P < 0.01). Free iron did not correlate with thiobarbituric acid-reactive substances. However, a significant correlation was found between lipid peroxidation and clinical severity (APACHE II) score (r = 0.54, P < 0.05). CONCLUSIONS: The present study provides evidence of lipid peroxidation in patients who die with septic shock. The data suggest that iron-catalysed hydroxyl radical generation does not form an important contribution to this lipid peroxidation in patients with sepsis.

APACHE↗
PubMed1996

Ascorbyl radical formation in patients with sepsis: effect of ascorbate loading.

Patients with sepsis have low concentrations of antioxidants, including ascorbic acid, and also have increased concentrations of markers of free radical damage. Although ascorbic acid is a potent antioxidant, it can act as a prooxidant by promoting iron-catalysed reactions. We measured baseline total vitamin C and bleomycin-detectable "free" iron levels and ascorbyl radical concentrations before and after intravenous infusion of 1 g ascorbic acid in patients with sepsis and healthy control subjects. Vitamin C concentrations were decreased in patients compared to healthy subjects (p < 0.0001), and "free" iron was increased (p < 0.002). Preinfusion ascorbyl radical concentrations were not different in patients and controls. Postinfusion ascorbyl radical levels increased in both controls and patients, with larger increases in healthy subjects (p < 0.0001), suggesting suboptimal basal vitamin C levels and increased scavenging of a constant oxidant pool by ascorbate in the controls. In the patients, who were all vitamin C deficient, infused ascorbate was rapidly consumed, either via the promotion of redox cycling of iron or as a result of radical scavenging. This study demonstrates markedly different handling of infused ascorbate in patients with sepsis and healthy subjects, and further studies are needed to elucidate the relative anti- and pro-antioxidant mechanisms of ascorbate in patients with raised "free" iron levels.

Anti-Bacterial Agents↗
PubMed1996

Regulation of nitric oxide synthase activity in cultured human endothelial cells: effect of antioxidants.

Nitric oxide release is induced in many cells, including vascular endothelium, as part of the host response to inflammation. Nitric oxide synthase activity is increased in patients with sepsis, associated with increased oxidant demands and decreased antioxidant protection. We used a human vascular endothelial cell line to investigate the influence of antioxidants on nitric oxide synthase activity. Cells were cultured to confluence and incubated with interferon gamma, tumor necrosis factor, and lipopolysaccharide in the combined presence of the antioxidants ascorbic acid, Trolox, catalase, or superoxide dismutase, singly and in combination, for 48 h. Additionally, some cells were incubated with hypoxanthine-xanthine oxidase or a nitric oxide donor. Nitric oxide synthase activity was upregulated by cytokine exposure (p < .0005). Ascorbic acid and superoxide dismutase/ catalase resulted in decreased enzyme activity (p < .05). Superoxide anion release from xanthine oxidase caused increased activity (p < .05) and exogenous nitric oxide tended to suppress synthase activity. We suggest that antioxidants scavenge superoxide anion, enabling feedback inhibition of nitric oxide synthase activity by nitric oxide, and thus reducing enzyme activity. Exogenous nitric oxide also has a similar effect. Superoxide generation suppresses this feedback inhibition. This study has important implications in patients with sepsis in whom nitric oxide synthase inhibitor therapy is currently under investigation.

Animals↗