Gene/Protein Disease Symptom Drug Enzyme Compound
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Query: UMLS:C0243026 (sepsis)
 52,417 document(s) hit in 31,850,051 MEDLINE articles (0.00 seconds)

Alterations in alveolar macrophage (AM) function during sepsis-induced hypoxia may influence tumor necrosis factor (TNF) secretion and the progression of acute lung injury. Nuclear factor (NF)-kappaB is thought to regulate the expression of endotoxin [lipopolysaccharide (LPS)]-induced inflammatory cytokines such as TNF, and NF-kappaB may also be influenced by changes in O2 tension. It is thus proposed that acute changes in O2 tension surrounding AMs alter NF-kappaB activation and TNF secretion in these lung cells. AM-derived TNF secretion and NF-kappaB expression were determined after acute hypoxic exposure of isolated Sprague-Dawley rat AMs. Adhered AMs (10(6)/ml) were incubated (37 degrees C at 5% CO2) for 2 h with LPS (Pseudomonas aeruginosa, 1 microgram/ml) in normoxia (21% O2-5% CO2) or hypoxia (1.8% O2-5% CO2). AM-derived TNF activity was measured with a TNF-specific cytotoxicity assay. Electrophoretic mobility shift and supershift assays were used to determine NF-kappaB activation and to identify NF-kappaB isoforms in AM extracts. In addition, mRNAs for selected AM proteins were determined with RNase protection assays. LPS-exposed AMs in hypoxia had higher levels of TNF (P < 0.05) and enhanced expression of NF-kappaB (P < 0.05); the predominant isoforms were p65 and c-Rel. Increased mRNA bands for TNF-alpha, interleukin-1alpha, and interleukin-1beta were also observed in the hypoxic AMs. These results suggest that acute hypoxia in the lung may induce enhanced NF-kappaB activation in AMs, which may result in increased production and release of inflammatory cytokines such as TNF.
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PMID:Acute hypoxia increases alveolar macrophage tumor necrosis factor activity and alters NF-kappaB expression. 1036 14

Increased intraperitoneal pressure and insufflation of carbon dioxide during laparoscopy may cause sepsis by promoting systemic inflammation in patients with intra-abdominal inflammatory diseases. The influence of carbon dioxide and helium during laparoscopy on bacteremia, endotoxemia, the plasma concentration of tumor necrosis factor-alpha (TNF-alpha), TNF-alpha secretion ex vivo by peripheral blood mononuclear cells (PBMCs), and intraperitoneal abscess formation was investigated in an animal model. A standardized fecal inoculum was injected intraperitoneally, and rats underwent laparoscopy with either carbon dioxide (N = 20) or helium (N = 20) or no further manipulation (control group; N = 20). Bacteremia was significantly more common 1 hour after laparoscopy with CO2 than in animals receiving helium or the control group. Furthermore, helium use led to a significant decrease of bacteremia 1 week after intervention. Fecal inoculation caused significant leukocytopenia in all groups within 1 hour after intervention, with complete recovery only in the helium-treated group (p < 0.05). The TNF-alpha plasma concentration was significantly lower in the helium-treated group, and suppression of ex vivo production recovered only in the animals undergoing laparoscopy with helium (p < 0.05). The number of intraperitoneal abscesses was significantly lower after laparoscopy with helium (2+/-1.5) than after CO2 laparoscopy (6.3+/-5.1) or in the control group (5.2+/-4.8). Laparoscopy with CO2 increased systemic inflammation only slightly, while helium use was associated with a significant lower incidence of bacteremia and local and systemic inflammation compared with the control group.
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PMID:Impact of laparoscopy with carbon dioxide versus helium on local and systemic inflammation in an animal model of peritonitis. 1041 52

We studied the effect of carbon dioxide (CO2) pneumoperitoneum on the systemic and peritoneal cytokine response in a rat model of intraperitoneal sepsis. After intraperitoneal injection of bacterial lipopolysaccharide (LPS, 10 mg/kg), rats were divided into 3 groups (n = 49 in each group): control (abdominal puncture); CO2 pneumoperitoneum, and laparotomy. Blood and peritoneal lavage fluid (PLF) were sampled at 0, 1, 2, 3, 4, 6, and 8 h after LPS challenge. Blood cell counts, plasma endotoxin level, and the levels of tumor necrosis factor-alpha (TNF-alpha), interleukin-1beta (IL-1beta), and interleukin-6 (IL-6) in the plasma and PLF were measured. Blood cell counts did not differ between the 3 groups. Plasma endotoxin levels in the pneumoperitoneum group were significantly increased immediately after the procedure (p < 0.05). Although peak plasma TNF-alpha levels in the pneumoperitoneum group were seen immediately after the procedure, other changes in plasma cytokine levels did not differ significantly between the 3 groups. PLF TNF-alpha and IL-1beta levels in the pneumoperitoneum group were significantly lower than levels in the control and laparotomy groups soon after the procedure (p < 0.05). PLF IL-6 levels in the pneumoperitoneum group tended to be lower than those in the laparotomy group. In conclusion, CO2 pneumoperitoneum might induce different responses between systemic and peritoneal cytokines soon after the procedure in a rat model of intraperitoneal sepsis.
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PMID:Effect of CO2 pneumoperitoneum on the systemic and peritoneal cytokine response in a LPS-induced sepsis model. 1139 71

Although numerous studies have provided evidence that the inflammatory cytokines TNF-alpha and IL-1beta have significant negative inotropic effects, the role of the interleukins in burn-mediated cardiac dysfunction has not been defined. Furthermore, most studies examining the cardiotoxic effects of inflammatory cytokines have ignored the complex inflammatory milieu that occurs in the intact subject with trauma, sepsis, or ischemic heart disease. Therefore, this study examined the time course of IL-1beta and IL-6 secretion by cardiomyocytes after burn trauma, and additional studies examined the effects of these cytokines alone or in combination with TNF-alpha on cardiac contractile performance (Langendorff). Sprague-Dawley rats were given a full thickness burn injury over 40% of the total body surface area; fluid resuscitation was lactated Ringers solution, 4 mL/kg per burn percentage of burn area. Sham burn animals received identical anesthesia and handling, but no burn injury. Rats were sacrificed at several different times postburn, and isolated hearts (n = 4-5 rats/group/time period) were perfused with collagenase-containing buffer to prepare cardiomyocytes or were perfused in vitro to examine cardiac contractile function (n = 5-6 rats/group/time period). Additional naive control rats (n = 10) were included to prepare cardiomyocytes that, in turn, were challenged with different concentrations of either IL-1beta, IL-6, or TNF-alpha alone or in combination for several time periods (CO2 incubator at 37 degrees C for 1-3 h). Finally, inflammatory cytokines alone or in combination were added to the perfusate of hearts isolated from additional control rats (n = 6-7/group) to assess the cardiac contraction and relaxation effects of cytokine challenge. Despite aggressive fluid resuscitation, burn trauma produced a time-related increase in cardiomyocyte secretion of IL-1beta, IL-6, and TNF-alpha. Exposure of naive cardiomyocytes prepared from control rats to each cytokine alone or combined cytokine challenge produced a time-dependent and concentration-dependent decrease in cell viability and an increase in supernatant creatine kinase levels. Either IL-1beta or TNF-alpha produced greater cardiac defects than IL-6 when added separately to Langendorff-perfused hearts; dysfunction was maximal with combined cytokine challenge (IL-1beta plus TNF-alpha plus IL-6). The data confirm that burn trauma upregulates inflammatory cytokine secretion by cardiomyocytes and suggest that these inflammatory cytokines act in concert to produce burn-mediated cardiac contractile dysfunction.
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PMID:IL-1beta and IL-6 act synergistically with TNF-alpha to alter cardiac contractile function after burn trauma. 1239 81

Deliberate induction of prophylactic hypercapnic acidosis protects against lung injury after in vivo ischemia-reperfusion and ventilation-induced lung injury. However, the efficacy of hypercapnic acidosis in sepsis, the commonest cause of clinical acute respiratory distress syndrome, is not known. We investigated whether hypercapnic acidosis--induced by adding CO2 to inspired gas--would be protective against endotoxin-induced lung injury in an in vivo rat model. Prophylactic institution of hypercapnic acidosis (i.e., induction before endotoxin instillation) attenuated the decrement in arterial oxygenation, improved lung compliance, and attenuated alveolar neutrophil infiltration compared with control conditions. Therapeutic institution of hypercapnic acidosis, that is, induction after endotoxin instillation, attenuated the decrement in oxygenation, improved lung compliance, and reduced alveolar neutrophil infiltration and histologic indices of lung injury. Therapeutic hypercapnic acidosis attenuated the endotoxin-induced increase in the higher oxides of nitrogen and nitrosothiols in the lung tissue and epithelial lining fluid. Lung epithelial lining fluid nitrotyrosine concentrations were increased with hypercapnic acidosis. We conclude that hypercapnic acidosis attenuates acute endotoxin-induced lung injury, and is efficacious both prophylactically and therapeutically. The beneficial actions of hypercapnic acidosis were not mediated by inhibition of peroxynitrite-induced nitration within proteins.
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PMID:Hypercapnic acidosis attenuates endotoxin-induced acute lung injury. 1469 4

Energy balance is the difference between energy consumed and total energy expended. Over a given period of time it expresses how much the body stores of fat, carbohydrate and protein will change. For the critically-ill patient, who characteristically exhibits raised energy expenditure and proteolysis of skeletal muscle, energy balance information is valuable because underfeeding or overfeeding may compromise recovery. However, there are formidable difficulties in measuring energy balance in these patients. While energy intake can be accurately recorded in the intensive care setting, the measurement of total energy expenditure is problematic. Widely used approaches, such as direct calorimetry or doubly-labelled water, are not applicable to the critically ill patient. Energy balance was determined over periods of 5-10 d in patients in intensive care by measuring changes in the fat, protein and carbohydrate stores of the body. Changes in total body fat were positively correlated with energy balance over the 5 d study periods in patients with severe sepsis (n 24, r 0.56, P = 0.004) or major trauma (n 24, r 0.70, P < 0.0001). Fat oxidation occurred in patients whose energy intake was insufficient to achieve energy balance. Changes in body protein were independent of energy balance. These results are consistent with those of other researchers who have estimated total energy requirements from measurements of O2 consumption and CO2 production. In critically-ill patients achievement of positive non-protein energy balance or total energy balance does not prevent negative N balance. Nutritional therapy for these patients may in the future focus on glycaemic control with insulin and specialised supplements rather than on energy balance per se.
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PMID:Energy balance in critical illness. 1450 3

Sepsis is a complex syndrome characterized by simultaneous activation of inflammation and coagulation in response to microbial insult. These events manifest as systemic inflammatory response syndrome (SIRS)/sepsis symptoms through release of proinflammatory cytokines, procoagulants, and adhesion molecules from immune cells and/or damaged endothelium.Conventional treatments have focused on source control, antimicrobials, vasopressors, and fluid resuscitation; however, a new treatment paradigm exists: that of treating the host response to infection with adjunct therapies including early goal directed therapy, drotrecogin alfa (activated), and immunonutrition. The multimechanistic drotrecogin alfa (activated) has been shown to reduce mortality in the severely septic patient when combined with traditional treatment. Therapies targeting improved oxygen and blood flow and reduction of apoptosis and free radicals are under investigation. Early sepsis diagnosis through detection of pro calcitonin, C reactive protein, sublingual CO2, and genetic factors may be beneficial. Ultimately, intervention timing may be the most important factor in reducing severe sepsis mortality.
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PMID:The puzzle of sepsis: fitting the pieces of the inflammatory response with treatment. 1476 63

Although protein carbonyl formation is an index of oxidative stress in skeletal muscles, the exact proteins, which undergo oxidation in these muscles, remain unknown. We used 2D electrophoresis, immunoblotting, and mass spectrometry to identify carbonylated proteins in the diaphragm in septic animals. Rats were injected with saline (control) or Escherichia coli lipopolysaccharides (LPS) and killed after various intervals. Diaphragm protein carbonylation increased significantly and peaked 12 h after LPS injection, and it was localized both inside muscle fibers and in blood vessels supplying muscle fibers. Aldolase A, glyceraldehyde 3-phosphate dehydrogenase, enolase 3beta, mitochondrial and cytosolic creatine kinases, alpha-actin, carbonic anyhdrase III, and ubiquinol-cytochrome c reductase were all carbonylated in septic rat diaphragms. In addition, we found significant negative correlations between the intensity of carbonylation and creatine kinase and aldolase activities. We conclude that glycolysis, ATP production, CO2 hydration, and contractile proteins are targeted by oxygen radicals inside the diaphragm during sepsis.
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PMID:Protein carbonyl formation in the diaphragm. 1547 39

The rises in tissue partial pressure of carbon dioxide have been observed in critically ill patients with shock and sepsis for a long time and have been proposed to be an earlier and more reliable marker of tissue hypoxia than traditional markers. However, the mechanisms leading to those increases, especially in sepsis and endotoxemia, are not well understood. Recent studies provided further data, supporting the idea that the origin of those increases in partial pressure of CO2 in sepsis as being caused by microcirculatory perfusion deficit resulting in mitochondrial depression by time. Previously, we have termed this condition where despite correction of systemic oxygen delivery variables, regional hypoxia and oxygen extraction deficit persist as microcirculatory and mitochondrial distress syndrome (MMDS). Recent findings support the idea that the progression from early to severe sepsis is accompanied or possibly even caused by microcirculatory dysfunction, which leads to mitochondrial dysfunction by time. Therefore early identification of microcirculatory dysfunction and correction with microcirculatory recruitment maneuvers are needed to ensure adequate microcirculatory perfusion and tissue oxygenation. Microcirculatory imaging, such as SDF imaging technique, appears to be a very useful tool for this task and its combination together with other systemic and regional tissue oxygenation measurements may provide more information regarding the tissue oxygenation and will be a very promising tool for microcirculatory researchers and the management of critically ill patients at the bedside.
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PMID:Microcirculatory recruitment maneuvers correct tissue CO2 abnormalities in sepsis. 1668 24

We investigated whether tissue hypoxia in sepsis produces substantial modifications of convective airway washout and consequently of CO2 transit time. Single breath tracing for carbon dioxide (SBT-CO2) was analysed in 18 ICU septic patients. Nine patients had tissue hypoxia events. Using the Hill formula, all tracings were analysed point by point to obtain the time required for CO2 to achieve 50% maximal value and the Fractional Expiratory Time 50 (FET0.5). Hypoxic patients FET0.5 and CO2 clearance were compared with non-hypoxic patients data. In hypoxic group CvCO2, CO2 clearance and FET0.5 values were higher than in non hypoxic group. During the recovery from hypoxia capnographic parameters did not differ from those recorded in the hypoxic period. CO2 clearance, but not FET0.5, correlated with arterial lactate and base excess either in hypoxic or in recovery period. In conclusion in septic patients tissue hypoxia influences CO2 elimination, modifying SB-CO2 tracing and lengthening FET0.5.
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PMID:Single breath tracing for carbon dioxide in septic patients with tissue hypoxia. 1772 66


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