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J A Carcillo

Publications and source records attributed to J A Carcillo.

At least 19 recordsLinked to original sources
PubMed1998

Quantification of G protein mRNA using reverse transcription and competitive PCR with a colorimetric microplate assay.

This paper reports an assay for the quantification of levels of specific mRNA for the alpha subunits of the inhibitory G proteins G alpha i-1, G alpha i-2, and G alpha i-3. The assay employs reverse transcription and competitive polymerase chain reaction (PCR) coupled to enzyme-linked oligonucleotide sorbent assay for differential detection and quantification of PCR products. The assay was conducted with conventional thermal block PCR cyclers as well as rapid air microcapillary cyclers. The detection stage consists of three steps using synthetic oligonucleotides, commercially available reagents and a conventional 96-well plate absorbance reader at settings of 450 and 630 nm. The assay is: (1) rapid, requiring about 3 h for quantification of PCR products; (2) safe, being non-radiometric; (3) relatively simple; (4) highly sensitive, being capable of detecting less than 10 initial copies of target cDNA; (5) precise, resolving two-fold differences in initial copy numbers of specific sequences as low as 10(-20) mol; (6) linear over a 3 log range, with two-fold differences in the quantity of cDNA producing consistent reductions in quantity of specific cDNA detected; and (7) reproducible, intra-assay and inter-assay coefficients of variation being 11.9 and 14.7%, respectively.

Animals↗
PubMed1998

Interstitial adenosine, inosine, and hypoxanthine are increased after experimental traumatic brain injury in the rat.

Adenosine is a putative neuroprotectant in ischemia, but its role after traumatic brain injury (TBI) is not clear. Metabolites of adenosine, particularly inosine and hypoxanthine, are markers of ischemia and energy failure. Adenosine triphosphate (ATP) breakdown early after injury and metabolism of cyclic adenosine monophosphate (cAMP) are potential sources of adenosine. Further delineation of the magnitude, location, time course, and source of production of adenosine after TBI is needed. We measured adenosine, inosine, and hypoxanthine in brain interstitial fluid after controlled cortical impact (CCI) in the rat. Rats (n = 15) were prepared for TBI induced by CCI. A microdialysis probe was placed in the cortex, and samples were collected every 10 min. After 3 h of equilibration, the catheter was removed, CCI was performed (4 m/sec, depth 2.5 mm), and the catheter was replaced. In the shams, the catheter was removed and replaced without CCI. The injury group included rats (n = 10) subjected to CCI. Within the injury group, the microdialysis probe was placed in the center of the eventual contusion (center, n = 5) or in the penumbral region (penumbra, n = 5). Purine metabolites were measured using ultraviolet-based high-pressure liquid chromatography. Adenosine, inosine, and hypoxanthine were dramatically increased after injury (61-fold, 37-fold, and 16-fold, respectively sham, all p < 0.05, two-way analysis of variance for repeated measures). No changes in cAMP were observed (p = 0.62 vs. sham). Adenosine peaked in the first 20 min and returned to near baseline 40 min, whereas inosine and hypoxanthine peaked at 30 min and remained increased for 40 min after CCI. Interstitial brain adenosine, inosine, and hypoxanthine were increased early after CCI in rats in the contusion and penumbra. ATP breakdown is a potential source of adenosine in this early period while metabolism of cAMP does not appear to play a role. Confirmation of these data in humans may suggest new strategies targeting this important metabolic pathway.

Adenosine↗
PubMed1998

Soluble adhesion molecules in CSF are increased in children with severe head injury.

Leukocyte-endothelial adhesion molecules, critical to the development of acute inflammation, are expressed in brain as part of the acute inflammatory response to traumatic brain injury (TBI). We measured the concentrations of the adhesion molecules P-selectin, ICAM-1, E-selectin, L-selectin, and VCAM-1 in ventricular cerebrospinal fluid (CSF) from children with severe TBI (Glasgow coma score < 8) and compared these findings with those from children with bacterial meningitis. P-selectin, an adhesion molecule associated with ischemia/reperfusion, was increased in children with TBI versus meningitis and control. Univariate and multivariate regression analyses demonstrated associations between CSF P-selectin and child abuse and age of < 4 years, and a significant, independent association between CSF intercellular adhesion molecule-1 (ICAM-1) and child abuse. These results are consistent with a specific acute inflammatory component to TBI in children. Future studies of secondary injury mechanisms and therapy after TBI should assess on the roles of P-selectin and ICAM-1 in injury and repair processes in brain after TBI.

Adolescent↗
PubMed1998

Plasma nitrite and nitrate concentrations and multiple organ failure in pediatric sepsis.

OBJECTIVE: To determine whether plasma nitrite and nitrate concentrations are associated with the development of sepsis-induced multiple organ failure. DESIGN: Prospective study. SETTING: University children's hospital. PATIENTS: Fifty-three consecutive children meeting criteria for sepsis and not receiving exogenous sources of nitric oxide. INTERVENTIONS: Plasma nitrite and nitrate concentrations were measured, and the number of organs failing was scored using an organ failure index on the first 3 days of sepsis. MEASUREMENTS AND MAIN RESULTS: Children with three or more organs failing on day 3 of sepsis had higher plasma nitrite and nitrate concentrations than children who had resolution of failure of three or more organs by day 3 of sepsis (days 2 and 3) and children who never had three organs failing in the first 3 days of sepsis (days 1, 2, and 3). Children who developed sequential pulmonary/hepatic/renal organ failure had significantly higher plasma nitrite and nitrate concentrations (days 1, 2, and 3). Nonsurvivors had significantly higher plasma nitrite and nitrate concentrations (days 2 and 3) than survivors. Plasma nitrite and nitrate concentrations on day 1 predicted the development of persistent failure of three of more organs and sequential multiple organ failure but not mortality. CONCLUSION: Increased plasma nitrite and nitrate concentrations are associated with the development of multiple organ failure in pediatric sepsis.

Adolescent↗
PubMed1998

Effect of the type IV phosphodiesterase inhibitor Ro 20-1724 on catecholamine-induced alterations in regional vascular resistance and regional blood flow.

Type IV phosphodiesterase inhibitors have been studied in multiple disease processes that commonly afflict patients who are treated with catecholamine infusions. To examine whether type IV phosphodiesterases alter catecholamine-induced changes in systemic and regional hemodynamic parameters, we examined the effects of Ro 20-1724 on rats during dobutamine, epinephrine, isoproterenol, and norepinephrine infusions. Twenty-six Sprague-Dawley rats received either Ro 20-1724 or vehicle. After central and regional hemodynamic monitoring was initiated, animals received increasing doses of two of the four catecholamines. In the absence of catecholamines, Ro 20-1724 infusion caused a significant increase in heart rate and a trend toward an increase in superior mesenteric artery blood flow. Ro 20-1724 attenuated the increase in blood pressure caused by epinephrine but had no effect on the dobutamine-, isoproterenol-, or norepinephrine-induced changes in blood pressure. Ro 20-1724 had no effect on catecholamine-induced changes in renal, carotid, and hindquarter vascular resistance but did attenuate the decrease in superior mesenteric artery vascular resistance caused by isoproterenol. Type IV phosphodiesterase inhibition in combination with catecholamines has no adverse effects on regional hemodynamics; however, it can inhibit the ability of epinephrine infusion to increase blood pressure.

4-(3-Butoxy-4-methoxybenzyl)-2-imidazolidinone↗
PubMed1998

Effects of type IV phosphodiesterase inhibition on cardiac function in the presence and absence of catecholamines.

Type IV phosphodiesterase (PDE4) inhibitors may be useful in several diseases in which catecholamine infusions are commonly used, including asthma, sepsis, and multiple organ failure. To determine whether type IV phosphodiesterase inhibitors alter baseline or catecholamine-induced changes in cardiac function or both, we examined the effects of Ro 20-1724 (PDE4 inhibitor) on several cardiac-performance parameters in the absence and presence of norepinephrine, epinephrine, isoproterenol, and dobutamine infusions (3, 1, 0.1, and 3 microg/kg/min, respectively). Male Sprague-Dawley rats received either Ro 20-1724 (10 microg/kg/min; n = 7) or vehicle (n = 6). After a left ventricular catheter was placed and connected to a heart-performance analyzer, each animal received each of the four catecholamines in randomized order (10 min per catecholamine with a 30-min washout period between infusions). In the absence of catecholamines, Ro 20-1724 significantly but mildly (i.e., <10%) increased heart rate but did not alter significantly any other measured cardiac parameter. In addition, Ro 20-1724 did not significantly alter norepinephrine-, epinephrine-, or dobutamine-induced changes in cardiac-performance parameters. There was, however, a significant attenuation of the isoproterenol-induced increase in a single measure of cardiac contractility (maximum dP/dt normalized to pressure). PDE4 inhibition does not cause significant cardiac toxicities in rats, both in the absence and presence of catecholamines. Our data suggest that PDE4 inhibitors may be safely used in critically ill patients receiving catecholamines. A clinical trial of this family of drugs in patients with critical illness is now being planned.

4-(3-Butoxy-4-methoxybenzyl)-2-imidazolidinone↗
PubMed1998

The compensatory anti-inflammatory cytokine interleukin 10 response in pediatric sepsis-induced multiple organ failure.

STUDY OBJECTIVES: To determine the circulating anti-inflammatory cytokine interleukin 10 (IL-10) response during the development of sepsis-induced multiple organ failure in children. DESIGN: Prospective study. SETTING: University pediatric ICU. PATIENTS: Fifty-three consecutive children with sepsis and 15 critically ill children without sepsis. INTERVENTIONS: Plasma IL-10, interleukin 6 (IL-6), and nitrite+nitrate (stable end products of nitric oxide) levels and an organ failure index (OFI indicating the number of failing organ systems) were determined in 53 children on days 1 to 3 of sepsis and in control children on day 1. The effect of exogenous human IL-10 or neutralizing IL-10 antibody on supernatant IL-6 levels in ex vivo whole blood culture from 17 children on day 1 of sepsis. MEASUREMENTS AND RESULTS: Children with three or more organ failures had higher plasma IL-10 levels than children with less than 3 organ failures (days 1 and 3; p<0.05). Children who developed sequential pulmonary/hepatic/renal failure had higher IL-10 levels (days 1 to 3; p<0.05). Nonsurvivors had higher IL-10 levels (day 3; p<0.05). IL-10 levels correlated with IL-6 levels (days 1 and 2) and nitrite+nitrate levels (days 1 and 3; p<0.05). Whole blood samples incubated ex vivo with exogenous recombinant human IL-10 had decreased supernatant IL-6 levels (p<0.05) and neutralizing IL-10 antibody showed no significant effect. CONCLUSION: A persistent compensatory anti-inflammatory cytokine response characterizes sepsis-induced multiple organ failure. Administration of exogenous IL-10 may inhibit the early proinflammatory response; however, identification of individual immune responsiveness and possibility of persistent infection could be important to rational use in the later stages of pediatric sepsis.

Adolescent↗
PubMed1998

Hemodynamic support in fluid-refractory pediatric septic shock.

OBJECTIVE: Assess outcome in children treated with inotrope, vasopressor, and/or vasodilator therapy for reversal of fluid-refractory and persistent septic shock. DESIGN: Survey; case series. SETTING: Three pediatric hospitals. PATIENTS: Fifty consecutive patients with fluid-refractory septic shock with a pulmonary artery catheter within 6 hours of resuscitation. INTERVENTIONS: Patients were categorized according to hemodynamic state and use of inotrope, vasopressor, and/or vasodilator therapy to maintain cardiac index (CI) >3.3 L/min/m2 and systemic vascular resistance >800 dyne-sec/cm/m to reverse shock. OUTCOME MEASURES: Hemodynamic state, response to class of cardiovascular therapy, and mortality. RESULTS: After fluid resuscitation, 58% of the children had a low CI and responded to inotropic therapy with or without a vasodilator (group I), 20% had a high CI and low systemic vascular resistance and responded to vasopressor therapy alone (group II), and 22% had both vascular and cardiac dysfunction and responded to combined vasopressor and inotropic therapy (group III). Shock persisted in 36% of the children. Of the children in group I, 50% needed the addition of a vasodilator, and in group II, 50% of children needed the addition of an inotrope for evolving myocardial dysfunction. Four children showed a complete change in hemodynamic state and responded to a switch from inotrope to vasopressor therapy or vice versa. The overall 28-day survival rate was 80% (group I, 72%; group II, 90%; group III, 91%). CONCLUSIONS: Unlike adults, children with fluid-refractory shock are frequently hypodynamic and respond to inotrope and vasodilator therapy. Because hemodynamic states are heterogeneous and change with time, an incorrect cardiovascular therapeutic regimen should be suspected in any child with persistent shock. Outcome can be improved compared with historical literature.

Adolescent↗
PubMed1998

Hypovolemic shock in pediatric patients.

Hypovolemic shock is a common disease treated in pediatric ICUs and emergency departments worldwide. A wide variety of etiologic factors may cause this disease, with the common net result of decreased intravascular volume leading to decreased venous return to the heart and decreased stroke volume. Inadequate perfusion results in impairment of delivery of nutrients and oxygen to vital end organs. With the advent of pediatric critical care and pediatric emergency medicine as specialties, deaths from hypovolemic shock have become increasingly rare in the United States. The physical signs of hypovolemic shock in children must be quickly recognized, and aggressive volume resuscitation must be administered before irreversible end-organ dysfunction occurs. This is best accomplished by large peripheral or central intravenous access, with intraosseous access an alternative option in the pediatric patient. The amount as well as the type of volume administered must be tailored for each individual patient, taking into account the amount of intravascular depletion and the disease state in which the shock has occurred. It is not uncommon for children to require large amounts of fluid for resuscitation, and close attention must be paid to children with fluid-refractory shock, who may require catecholamine and/or exogenous steroid support in combination with aggressive fluid resuscitation.

Adolescent↗
PubMed1998

The cytochrome P450 suicide inhibitor, 1-aminobenzotriazole, sensitizes rats to zymosan-induced toxicity.

Reduction in whole body cytochrome P450 (CYP 450) activity is evident in humans who develop trauma and sepsis-induced multiple organ failure (MOF). It is not known whether this has any deleterious or protective effect. Intraperitoneal injection of zymosan, the cell wall of Saccharomycoses A, induces dose-dependent inflammation with concomitant MOF in rats. High dose intraperitoneal zymosan (100 mg/100 g body weight) causes mortality and organomegaly in rats; low dose zymosan (20 mg/100 g body weight) does not. To study a role for CYP 450 in zymosan-induced toxicity, we examined the effect of the non-specific CYP 450 suicide inhibitor 1-aminobenzotriazole (1-ABT)(80 mg/kg/d), on rats treated with low dose zymosan. The 90% reduction in CYP 450 content achieved by this dose of 1-ABT was associated with 58% mortality in rats treated with low dose zymosan, in contrast to no mortality in rats treated with low dose zymosan alone (p < 0.01). In survivors, liver and lung organomegaly (p < 0.01), and polymorphonuclear leukocyte accumulation in the liver (p < 0.01) were increased after zymosan administration in rats treated with 1-ABT compared to those without 1-ABT. There was no effect of treatment with 1-ABT on the increased urinary excretion of nitric oxide byproducts observed after zymosan administration. These observations are consistent with the hypothesis that the CYP 450 enzyme system is an endogenous protectant in this experimental model of inflammation-induced MOF.

Animals↗
PubMed1997

Comparison of the interleukin-6 and interleukin-10 response in children after severe traumatic brain injury or septic shock.

Inflammation may play an important role in the evolution of damage after traumatic brain injury (TBI). IL-6 and IL-10 are markers of inflammation that are pro- and anti-inflammatory in nature, respectively. They have been used as an index of the degree of inflammation in diseases including sepsis and meningitis. We hypothesized that both IL-6 and IL-10 would be increased in the cerebrospinal fluid (CSF) of children after TBI. We measured ventricular CSF concentrations of these metabolites (ELISA) each of the first 3 days after TBI in 15 children. CSF IL-6 was increased on day 1 (p < 0.05 vs days 2 or 3). CSF IL-10 was similarly increased on day 1 (p < 0.05). CSF IL-6 after TBI is similar to serum IL-6 levels previously reported in children with septic shock. In contrast, the CSF IL-10 response was markedly attenuated following TBI compared to sepsis. These data suggest a unique balance between pro- and anti-inflammatory cytokines in brain after TBI.

Brain Injuries↗
PubMed1997

The role of adenosine during the period of delayed cerebral swelling after severe traumatic brain injury in humans.

Cerebrovascular failure with an increase in cerebral blood volume or hyperemia contributes delayed cerebral swelling after severe traumatic brain injury (TBI) in humans. One mediator that could be involved in this process is adenosine, which stimulates a concurrent reduction in cerebral metabolic rate and an increase in cerebral blood flow (CBF). We hypothesized that during the delayed phase after TBI in humans: 1) CSF adenosine concentration is associated with uncoupling of CBF and CMRO2, and 2) adenosine formation is driven by mediator-stimulated cAMP production in injured brain. We serially measured CBF and AVDO2, and CSF adenosine, lactate and cAMP after severe TBI in 13 humans. After 6-18 h, global CBF was increased and AVDO2 was reduced vs all other time periods, defining the uncoupling phase as the period between 18 h and 5 days. CSF adenosine concentration was negatively associated with AVDO2 and strongly associated with death (both p < 0.05), CSF lactate peaked during the initial 18 h, but remained increased for 5 days. CSF cAMP concentration was not increased (vs normal). The association between CSF adenosine concentration and death, and the correlation between uncoupling of CBF and oxidative metabolism and CSF adenosine concentration support our first hypothesis. In contrast, the low levels of cAMP in CSF observed in these patients, but persistently increased CSF lactate, refute our second hypothesis. We speculate that hyperglycolysis or occult ischemic foci are possible sources of ATP breakdown and adenosine formation, and that adenosine is playing a neuroprotective role.

Adenosine↗
PubMed1997

Septic shock.

Although our understanding of molecular events in septic shock is growing exponentially, bedside management has changed only incrementally over the last 20 years. In pediatric and adult patients alike, treatment continues to be largely supportive. Morbidity and mortality, though gradually improving, continue to be high. The major similarities, as well as the minor differences, between pediatric and adult septic shock are reviewed in this article, with an emphasis on current clinical practice and recent clinical investigations of novel therapies.

Adult↗
PubMed1997

Interleukin-6 and interleukin-10 in cerebrospinal fluid after severe traumatic brain injury in children.

Cytokines may play an important role in the pathophysiology of traumatic brain injury (TBI) in children. Interleukin-6 (IL-6) is a proinflammatory cyotkine that plays a role in regenerative processes within the central nervous system (CNS), whereas interleukin-10 (IL-10) is an antiinflammatory cytokine. Both have been measured in serum and cerebrospinal fluid (CSF) as an index of the degree of inflammation in diseases, including sepsis and meningitis. We hypothesized that both IL-6 and IL-10 would be increased in the CSF of children after severe TBI. Fifteen children who sustained severe TBI (Glascow Coma Score [GCS] < or = 7) were studied. Standard neurointensive care was provided. Ventricular CSF collected the first 3 days after TBI was analyzed for IL-6 and IL-10 concentrations by ELISA. Controls were 20 children who were evaluated for meningitis with diagnostic lumbar puncture subsequently found to have no CSF pleocytosis and negative cultures. IL-6 was increased in children after TBI versus controls on all days studied (day 1, 3158.2 +/- 621.8 pg/ml; day 2, 1111.6 +/- 337.0 pg/ml; day 3, 826.7 +/- 193.5 pg/ml vs. 20.6 +/- 5.8 pg/ml, p < 0.0001, Mann-Whitney Rank Sum). IL-10 was increased in children after TBI vs controls on all days studied (day 1, 47.2 +/- 12.9 pg/ml; day 2, 21.0 +/- 6.7 pg/ml; day 3, 15.5 +/- 5.9 pg/ml vs. 8.9 +/- 7.5 pg/ml, p < 0.01). Increased IL-10 concentrations were independently associated with age < 4 years and mortality (p = 0.004 and 0.04, respectively, multivariate linear model). This study demonstrates that IL-6 is increased after TBI in children to levels similar to those reported in adults and is the first to show that IL-10 is increased in CSF of humans after TBI. These data suggest that there may be an age-dependent production of IL-10 after TBI in children.

Adolescent↗
PubMed1997

Phosphodiesterases in the rat renal vasculature.

The objective this investigation was to determine the relative importance of type I, III, and IV phosphodiesterases in the regulation of cyclic adenosine monophosphate (cAMP) in the renal circulation. In the first experimental series, four groups of isolated rat kidneys perfused with Tyrode's solution were stimulated with isoproterenol (3 microM) and then treated with increasing concentrations (from the approximately IC50 to 30 times the approximately IC50 in threefold increments) of one of four phosphodiesterase inhibitors: group 1, 3-isobutyl-1-methylxanthine, a "broad-spectrum" phosphodiesterase inhibitor (10-300 microM); group 2, Ro 20-1724, a selective type IV phosphodiesterase inhibitor (3-100 microM); group 3, 8-methoxymethyl-3-isobutyl-1-methylxanthine, a selective type I phosphodiesterase inhibitor (3-100 microM); and group 4, milrinone, a selective type III phosphodiesterase inhibitor (0.3-10 microM). In the second experimental series, five groups of cultured preglomerular (interlobular and afferent arteriolar) vascular smooth-muscle cells were stimulated with isoproterenol (1 microM) and treated with vehicle or supramaximal concentrations (30 times IC50) of either 3-isobutyl-1-methylxanthine (300 microM), Ro 20-1724 (100 microM), 8-methoxymethyl-3-isobutyl-1-methylxanthine (100 microM), or milrinone (10 microM). In perfused kidneys and cultured pre-glomerular vascular smooth-muscle cells, 3-isobutyl-1-methylxanthine and Ro 20-1724 similarly increased renal cAMP release and total cellular (extracellular + intracellular) cAMP levels, respectively. In contrast, neither 8-methoxymethyl-3-isobutyl-1-methylxanthine nor milrinone affected renal cAMP release or total cellular cAMP levels. These data indicate that in the renal circulation, type IV phosphodiesterase is the predominant phosphodiesterase isozyme.

1-Methyl-3-isobutylxanthine↗
PubMed1997

Cerebrospinal fluid adenosine concentration and uncoupling of cerebral blood flow and oxidative metabolism after severe head injury in humans.

OBJECTIVE: Uncoupling of cerebral blood flow (CBF) and oxidative metabolism is observed after severe head injury in comatose patients; however, the mechanism(s) involved remain undefined. Adenosine can produce cerebral vasodilation and reduce neuronal activity and is a possible mediator of uncoupling. We hypothesized that cerebrospinal fluid (CSF) adenosine concentrations would be increased during uncoupling of CBF and oxidative metabolism, defined as a narrow arterio-jugular venous oxygen difference [D(a-v)O2 4 vol%] after head injury. METHODS: Adenosine concentrations were measured using fluorescent-based high-pressure liquid chromatography in 67 CSF samples obtained from 13 comatose (Glasgow Coma Scale score 7) adult patients who sustained a severe closed head injury. At the time each sample was obtained, CBF was measured by the xenon-133 method, and blood samples were obtained for determination of D(a-v)O2. RESULTS: CSF adenosine concentration was negatively associated with D(a-v)O2 (P < 0.05, generalized multivariate linear regression model). In addition, CSF adenosine concentration was increased when D(a-v)O2 was 4 versus > 4 vol% (38.5 [3.2-306.3] versus 14.0 [2.7-795.5] nmol/L, respectively, median [range]; P < 0.025) and in patients who died versus survivors (40.1 [6.9-306.3] versus 12.9 [2.7-795.5] nmol/L, respectively, median [range]; P < 0.001). CONCLUSION: The association between increased CSF adenosine concentration and a reduction in global cross-brain extraction of oxygen supports a regulatory role for adenosine in the complex balance between CBF and oxidative and nonoxidative metabolism severe head injury in humans.

Adenosine↗