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Bacterial toxins are widespread in the environment as well as in the digestive system of humans and animals. Toxin from Gram-negative bacteria (endotoxin or lipopolysaccharide; LPS) has a life-long programming effect on reproduction in rats, but the mediators have not been well-documented, so we investigated the effects of LPS on the timing of puberty in female rats. Because the levels of nitric oxide (NO) and interleukin 1β (IL-1β) increase following injection of LPS, we injected neonates (post-natal day (pnd) 7) with LPS, with or without NO or IL-1β inhibitors. Half of the prepubescent (pnd 30) animals received an additional LPS injection. Vaginal opening, number of ovarian follicles, and serum anti-LPS antibodies were determined. A single LPS injection was sufficient to reduce the primordial follicle pool, but puberty was delayed when rats received 2 LPS injections (at pnd 7 and 30). NO or IL-1β inhibitors improved both of these parameters, suggesting that the early detrimental effects of LPS on puberty and primordial follicle pool are mediated by NO and IL-1β. Key words: lipopolysaccharide, puberty, ovarian function, IL-1β, nitric oxide, female rats. Les toxines bacteriennes sont repandues dans l'environnement et dans le systeme digestif des humains et des animaux. On sait que la toxine des bacteries negatives a Gram (endotoxine ou lipopolysaccharide; LPS) exerce un effet de programmation sur la reproduction des rats qui dure toute la vie, mais ses mediateurs ne sont pas bien documentes. Puisque les niveaux d'oxyde nitrique (NO) et d'interleukine 1β (IL-1β) augmentent a la suite d'une injection de LPS, les auteurs ont examine les effets d'une injection neonatale de LPS (jour 7 postnatal) en presence ou non d'inhibiteurs de NO ou d'IL-1β, sur la maturation pubertaire de rats femelles. La moitie des animaux a recu une injection supplementaire de LPS en periode pre-pubertaire (jour 30 postnatal). L'ouverture vaginale, le nombre de follicules ovariens et la presence d'anticorps anti-LPS dans le serum ont ete determines. Une injection unique de LPS suffisait a reduire le pool de follicules primordiaux mais la puberte n'etait retardee que chez les rates ayant recu deux injections de LPS, aux jours 7 et 30 postnataux. Les inhibiteurs amelioraient les deux parametres, suggerant que les effets nocifs precoces du LPS sur la puberte et le pool de follicules primordiaux passent par l'intermediaire du NO et de l'IL-1β. [Traduit par la Redaction] Mots-cles: lipopolysaccharide, puberte, fonction ovarienne, IL-1β, oxyde nitrique, rats femelles., Introduction The environmental chemicals that have an impact on human health are not only man-made or man-introduced agents (Rylander 2002); humans are continuously exposed to toxins originating from microorganism-associated molecular [...]

Bacterial toxins are widespread in the environment as well as in the digestive system of humans and animals. Toxin from Gram-negative bacteria (endotoxin or lipopolysaccharide; LPS) has a life-long programming effect on reproduction in rats, but the mediators have not been well-documented, so we investigated the effects of LPS on the timing of puberty in female rats. Because the levels of nitric oxide (NO) and interleukin 1β (IL-10) increase following injection of LPS, we injected neonates (post-natal day (pnd) 7) with LPS, with or without NO or IL-1β inhibitors. Half of the prepubescent (pnd 30) animals received an additional LPS injection. Vaginal opening, number of ovarian follicles, and serum anti-LPS antibodies were determined. A single LPS injection was sufficient to reduce the primordial follicle pool, but puberty was delayed when rats received 2 LPS injections (at pnd 7 and 30). NO or IL-1β inhibitors improved both of these parameters, suggesting that the early detrimental effects of LPS on puberty and primordial follicle pool are mediated by NO and IL-1β. Key words: lipopolysaccharide, puberty, ovarian function, IL-1β, nitric oxide, female rats. Les toxines bacteriennes sont repandues dans l'environnement et dans le systeme digestif des humains et des animaux. On sait que la toxine des bacteries negatives a Gram (endotoxine ou lipopolysaccharide; LPS) exerce un effet de programmation sur la reproduction des rats qui dure toute la vie, mais ses mediateurs ne sont pas bien documentes. Puisque les niveaux d'oxyde nitrique (NO) et d'interleukine 1β (IL-10) augmentent a la suite d'une injection de LPS, les auteurs ont examine les effets d'une injection neonatale de LPS (jour 7 postnatal) en presence ou non d'inhibiteurs de NO ou d'IL-1β, sur la maturation pubertaire de rats femelles. La moitie des animaux a recu une injection supplementaire de LPS en periode pre-pubertaire (jour 30 postnatal). L'ouverture vaginale, le nombre de follicules ovariens et la presence d'anticorps anti-LPS dans le serum ont ete determines. Une injection unique de LPS suffisait a reduire le pool de follicules primordiaux mais la puberte n'etait retardee que chez les rates ayant recu deux injections de LPS, aux jours 7 et 30 postnataux. Les inhibiteurs amelioraient les deux parametres, suggerant que les effets nocifs precoces du LPS sur la puberte et le pool de follicules primordiaux passent par l'intermediaire du NO et de l'IL-1β. [Traduit par la Redaction] Mots-cles: lipopolysaccharide, puberte, fonction ovarienne, IL-1β, oxyde nitrique, rats femelles., Introduction The environmental chemicals that have an impact on human health are not only man-made or man-introduced agents (Rylander 2002); humans are continuously exposed to toxins originating from microorganism-associated molecular [...]

Cirrhosis is associated with vascular dysfunction and endotoxemia. These experiments were designed to investigate the hypothesis that the administration of a low-dose of lipopolysaccharide (LPS) worsens vascular dysfunction in rats subjected to bile-duct ligation (BDL), and to determine whether LPS initiates changes in vascular Toll-like receptor 4 (TLR4) expression. Four weeks after BDL, the animals were given an intraperitoneal injection of either saline or LPS (1.0 mg/kg body mass). Three hours later, the superior mesenteric artery was isolated, perfused, and then subjected to the vasoconstriction and vasodilatation effects of phenylephrine and acetylcholine, respectively. Our results show that phenylephrine-induced vasoconstriction decreased in the cirrhotic vascular bed (BDL rats) compared with the vascular bed of the sham-operated animals, and that the LPS injections in the cirrhotic (BDL) rats worsened this response. LPS injection administered to the sham-operated animals had no such effect. On the other hand, both the BDL procedure and the LPS injection increased acetylcholine-induced vasorelaxation, but LPS administration to the BDL rats had no effect on this response. The mRNA levels of TLR4 did not change, but immunohistochemical studies showed that TLR4 localization switched from the endothelium to vascular smooth muscle cells following chronic BDL. In conclusion, acute endotoxemia in cirrhotic rats is associated with hyporesponsiveness to phenylephrine and tolerance to the effects of acetylcholine. Altered localization of TLR4 may be responsible for these effects. Key words: cirrhosis, endotoxin, Toll-like receptor 4, mesenteric artery, rats. La cirrhose est associee a une dysfonction vasculaire et une endotoxemie. Les presentes experiences visaient a etudier l'hypothese selon laquelle l'administration d'une faible dose de lipopolysaccharides (LPS) aggrave la dysfonction vasculaire dans un modele de rats soumis a une ligature du choledoque et d'observer si cette intervention induit des variations de l'expression vasculaire du gene TLR4 (pour << Toll-like receptor 4 >>). Quatre semaines apres la ligature du choledoque, on administrait aux animaux une solution saline ou des LPS (a 1,0 mg/kg de masse corporelle) par voie intraperitoneale. Trois heures plus tard, l'artere mesenterique superieure etait isolee, perfusee et soumise a une reponse de vasoconstriction ou de vasodilatation provoquee par l'administration de phenylephrine et d'acetylcholine, respectivement. Nos resultats ont montre que la vasoconstriction induite par la phenylephrine diminuait dans le lit vasculaire associe a une cirrhose comparativement a chez les animaux soumis a une intervention chirurgicale factice et que l'injection de LPS amplifiait cette reponse chez les rats cirrhotiques. L'injection de LPS ne modifiait pas la reponse chez les animaux soumis a une intervention chirurgicale factice. Par ailleurs, la ligature du choledoque ou l'injection de LPS augmentaient la vasorelaxation induite par l'acetylcholine, mais l'injection de LPS ne parvenait pas a modifier la reponse chez les rats soumis a une ligature du choledoque. Toutefois, les taux d'ARNm du gene TLR4 ne changeaient pas, mais des etudes d'immunohistochimie ont montre que la localisation du gene TLR4 passait de l'endothelium aux cellules musculaires lisses vasculaires pendant la phase chronique de ligature du choledoque. En conclusion, chez les rats cirrhotiques, l'endotoxemie est associee a une diminution de la reponse a la phenylephrine et a la tolerance aux effets de l'acetylcholine. Les reponses observees pourraient etre attribuables a une modification de la localisation du gene. [Traduit par la Redaction] Mots-cles : cirrhose, endotoxine, Toll-like receptor 4, artere mesenterique, rats., Introduction Liver cirrhosis is one of the principle causes of morbidity and mortality in the world. With this pathological condition there is an imbalance between vasoconstrictors and vasodilators (Vallance and [...]

Author(s): Peter Pickkers [sup.1] , Didier Payen [sup.2] Author Affiliations: (1) 0000 0004 0444 9382, grid.10417.33, Department of Intensive Care Medicine (710), Radboud University Medical Centre, , P.O. Box 9101, [...]

Bacterial LPS (endotoxin) has been implicated in the pathogenesis of acute liver disease through its induction of the proinflammatory cytokine TNF-α. TNF-α is a key determinant of the outcome in [...]

Acute myocardial dysfunction is a typical manifestation of septic shock. Experimentally, the administration of endotoxin [lipopolysacharride (LPS)] to laboratory animals is frequently used to study such dysfunction. However, a majority of studies used load-dependent indexes of cardiac function [including ejection fraction (EF) and maximal systolic pressure increment (dP/[dt.sub.max])], which do not directly explore cardiac inotropism. Therefore, we evaluated the direct effects of LPS on myocardial contractility, using left ventricular (LV) pressure-volume catheters in mice. Male BALB/c mice received an intraperitoneal injection of E. coli LPS (1, 5, 10, or 20 mg/kg). After 2, 6, or 20 h, cardiac function was analyzed in anesthetized, mechanically ventilated mice. All doses of LPS induced a significant drop in LV stroke volume and a trend toward reduced cardiac output after 6 h. Concomitantly, there was a significant decrease of LV preload (LV end-diastolic volume), with no apparent change in LV afterload (evaluated by effective arterial elastance and systemic vascular resistance). Load-dependent indexes of LV function were markedly reduced at 6 h, including EF, stroke work, and dP/[dt.sub.max]. In contrast, there was no reduction of load-independent indexes of LV contractility, including end-systolic elastance (ejection phase measure of contractility) and the ratio dP/[dt.sub.max]/end-diastolic volume (isovolumic phase measure of contractility), the latter showing instead a significant increase after 6 h. All changes were transient, returning to baseline values after 20 h. Therefore, the alterations of cardiac function induced by LPS are entirely due to altered loading conditions, but not to reduced contractility, which may instead be slightly increased. cardiac function; contractility; mice doi: 10.1152/ajpheart.01135.2009.

Activated protein C (APC), the only FDA-approved biotherapeutic drug for sepsis, possesses anticoagulant, antiinflammatory, and barrier-protective activities. However, the mechanisms underlying its antiinflammatory functions are not well defined. Here, we report that the antiinflammatory activity of APC on macrophages is dependent on integrin CD11b/CD18, but not on endothelial protein C receptor (EPCR). We showed that CD11b/CD18 bound APC within specialized membrane microdomains/lipid rafts and facilitated APC cleavage and activation of protease-activated receptor-1 (PAR1), leading to enhanced production of sphingosine-1-phosphate (S1P) and suppression of the proinflammatory response of activated macrophages. Deletion of the γ-carboxyglutamic acid domain of APC, a region critical for its anticoagulant activity and EPCR-dependent barrier protection, had no effect on its antiinflammatory function. Genetic inactivation of CD11b, PAR1, or sphingosine kinase-1, but not EPCR, abolished the ability of APC to suppress the macrophage inflammatory response in vitro. Using an LPS-induced mouse model of lethal endotoxemia, we showed that APC administration reduced the mortality of wild-type mice, but not CD11b-deficient mice. These data establish what we believe to be a novel mechanism underlying the antiinflammatory activity of APC in the setting of endotoxemia and provide clear evidence that the antiinflammatory function of APC is distinct from its barrier-protective function and anticoagulant activities., Introduction As many as 500,000 individuals in the US develop sepsis each year, from a variety of offending pathogens, and as many as half these cases are fatal. Prominent features [...]

Prenatal exposures to immunogenic stimuli, such as bacterial LPS, have shown to influence the neonatal immune system and lung function. However, no detailed analysis of the immunomodulatory effects of LPS on postnatal T helper cell differentiation has been performed. Using a rat model, we investigated the effect of prenatal LPS exposure on postnatal T cell differentiation and experimental allergic airway disease. Pregnant rats were injected with LPS on day 20 and 21 (term = 22 days). Some of the offspring were sensitized and challenged with ovalbumin. Positive control animals were placebo exposed to saline instead of LPS, whereas negative controls were sensitized with saline. Expression of T cell-related transcription factors and cytokines was quantified in the lung, and airway hyperresponsiveness was measured. Prenatal LPS exposure induced a T helper 1 ([T.sub.H]1) immune milieu in the offspring of rats [i.e., increased T-bet and [T.sub.H]1 cytokine expression while expression of [T.sub.H]2-associated transcription factors (GATA3 and STAT6) and cytokines was decreased]. Prenatal LPS exposure did not trigger [T.sub.H]17 cell differentiation in the offspring. Furthermore, prenatal LPS exposure reduced ovalbumin-induced ([T.sub.H]2-mediated) airway inflammation, eosinophilia, and airway responsiveness. Thus, in utero exposure to endotoxin promotes a [T.sub.H]1 immune environment, which suppresses the development of allergic airway disease later in life. asthma; lipopolysaccharide; pulmonary inflammation; ovalbumin; airway hyperresponsiveness doi: 10.1152/ajplung.00399.2009.

The impact of endotoxemia on cerebral endothelium and cerebral blood flow (CBF) regulation was studied in conscious newborn lambs. Bacterial endotoxin [LPS, 2 [micro]g/kg iv] was infused on 3 consecutive days. Cerebrovascular function was assessed by monitoring CBF and cerebral vascular resistance (CVR) over 12 h each day and by the endothelium-dependent vasodilator bradykinin (BK) (n = 10). Inflammatory responses were assessed by plasma tumor necrosis factor-[alpha] (TNF-[alpha], n = 5). Acutely, LPS disrupted the cerebral circulation within l h, with peak cerebral vasoconstriction at 3 h (CBF -28 and CVR +118%, P < 0.05) followed by recovery to baseline by 12 h. TNF-[alpha] and body temperature peaked ~1 h post-LPS. BK-induced vasodilatation (CVR -20%, P < 0.05) declined with each LPS infusion, was abolished after 3 days, and remained absent for at least the subsequent 5 days. Histological evidence of brain injury was found in four of five LPS-treated newborns. We conclude that endotoxin impairs cerebral perfusion in newborn lambs via two mechanisms: 1) acute vasoconstriction (over several hours); and 2) persistent endothelial dysfunction (over several days). Endotoxin-induced circulatory impairments may place the newborn brain at prolonged risk of CBF dysregulation and injury as a legacy of endotoxin exposure. cerebral blood flow; cerebral endothelial function doi:10.1152/ajpregu.00398.2009

Lipopolysaccharide (LPS) is an important factor in sepsis. LPS given by intraperitoneal injection induces intestinal hyperpermeability and bacterial translocation in animals and stimulates hepatic Kupffer cells to release TNF-[alpha] into the bile. This study aims to test the hypothesis that in response to LPS stimulation, hepatic Kupffer cells and extrahepatic macrophages release a large amount of the inflammatory cytokine high-mobility group box 1 (HMGB1) into the bile and that bile containing HMGB 1 contributes to gut barrier dysfunction in experimental endotoxemia. To test this, rat common bile ducts were catheterized and bile flow rate was monitored before and during the LPS administration. Eight hours after LPS challenge, anti-HMGB1 neutralizing antibody or nonimmune (sham) IgG was injected into the duodenal lumen of endotoxemic rats; normal mice were also gavaged with normal or endotoxemic rat bile (bile collected from LPS-treated rats). We found that after LPS challenge, the bile flow rate in rats was significantly decreased at the 4- to 12-h time points, TNF-[alpha] concentration in the bile was markedly elevated at the 3- to 4-h time points, and bile HMGB1 levels were significantly increased at the 8- to 12-h time points. Duodenal injection with anti-HMGB1 antibody reversed LPS-induced gut barrier dysfunction in rats. In addition, feeding endotoxemic rat bile to normal mice significantly increased both mucosal permeability and bacterial translocation. The increase in permeability and bacterial translocation was reversible following removal of HMGB1 from the endotoxemic rat bile. These findings document that bile HMGB1 mediates gut barrier dysfunction in experimental endotoxemia. endotoxemia; gut barrier function

Infections produce severe respiratory muscle dysfunction. It is known that the proteasome proteolytic system is activated in skeletal muscle in sepsis, and it has been postulated that this degradative pathway is responsible for inducing skeletal muscle weakness and wasting. The objective of this study was to determine if administration of proteasomal inhibitors (MGI32, epoxomicin, bortezomib) can prevent sepsis-induced diaphragm weakness. Rats were given either 1) saline (0.5 ml ip), 2) endotoxin (12 mg/kg ip), 3) endotoxin plus MG132 (2.5 mg/kg), 4) endotoxin plus epoxomicin (1 [micro]mo1/kg), or 5) endotoxin plus bortezomib (0.05 mg/kg). Animals were killed either 48 or 96 h after injections, and assessments were made of diaphragm proteolysis, force-frequency relationships, mass, protein content, and caspase activation. Endotoxin increased proteolysis (P caspase; sepsis; skeletal muscle

BACKGROUND: The relationship of domestic endotoxin exposure to allergy and asthma has been widely investigated. However, few studies have evaluated predictors of household endotoxin, and none have done so for [...]

Byline: Stephanie Wolff (1), Sabine Klatt (1), Jens C. Wolff (2), Jochen Wilhelm (3), Ludger Fink (3), Manfred Kaps (1), Bernhard Rosengarten (1) Keywords: Sepsis; Delirium; Encephalopathy; Hippocampus; Chemokines; Microarrays Abstract: Purpose We studied gene expression differences in brain homogenate, hippocampus, somatosensory cortex and cerebellum of rats suffering from sepsis-associated delirium and analyzed the effects of norepinephrine and 1,400 W (specific inhibitor of the inducible nitric-oxide synthase). Methods We applied microarray screenings to rat brain homogenate 1, 3 and 4.5 h after lipopolysaccharide (LPS, 5 mg/kg) or 0.9% NaCl treatment. Therapy groups were analyzed after 4.5 h. Validations and compartment specific investigations were carried out by real-time PCR. Results Most striking gene expression differences were seen 4.5 h after LPS administration, especially within the hippocampus (chemokines and endothelial cell-specific molecule 1). Norepinephrine resulted in a discrete chemokine up-regulation, while 1,400 W had hardly any effect. Conclusion Strongest gene regulations were found within the hippocampus. Norepinephrine showed a tendency of having a proinflammatory influence, while 1,400 W had no clear-cut effect onto the gene expression level. Author Affiliation: (1) Department of Neurology, Justus-Liebig-University Giessen, Am Steg 14, 35392, Giessen, Germany (2) Max-Planck-Institute for Heart and Lung Research, 61231, Bad Nauheim, Germany (3) Department of Pathology, Justus-Liebig-University Giessen, 35392, Giessen, Germany Article History: Registration Date: 05/01/2009 Received Date: 06/06/2008 Accepted Date: 10/11/2008 Online Date: 21/01/2009 Article note: This article is discussed in the editorial available at: doi: 10.1007/s00134-009-1395-6.

We studied the impact of endotoxemia on cerebral blood flow (CBF), cerebral vascular resistance (CVR), and cerebral oxygen transport ([O.sub.2] transport) in fetal sheep. We hypothesized that endotoxemia impairs CBF regulation and [O.sub.2] transport, exposing the brain to hypoxicischemic injury. Responses to lipopolysaccharide (LPS; 1 [micro]g/kg iv on 3 consecutive days, n = 9) or normal saline (n = 5) were studied. Of LPS-treated fetuses, five survived and four died; in surviving fetuses, transient cerebral vasoconstriction at 0.5 h ([DELTA]CVR approximately +50%) was followed by vasodilatation maximal at 5-6 h ([DELTA]CVR approximately -50%) when CBF had increased (approximately +60%) despite reduced ABP (approximately -20%). Decreased CVR and increased CBF persisted 24 h post-LPS and the two subsequent LPS infusions. Cerebral 02 transport was sustained, although arterial [O.sub.2] saturation was reduced (P < 0.05). Histological evidence of neuronal injury was found in all surviving LPS-treated fetuses; one experienced grade IV intracranial hemorrhage. Bradykinin-induced cerebral vasodilatation ([DELTA]CVR approximately -20%, P < 0.05) was abolished after LPS. Fetuses that died post-LPS (n = 4) differed from survivors in three respects: CVR did not fall, CBF did not rise, and [O.sub.2] transport fell progressively. In conclusion, endotoxin disrupts the cerebral circulation in two phases: 1) acute vasoconstriction (1 h) and 2) prolonged vasodilatation despite impaired endothelial dilatation (24 h). In surviving fetuses, LPS causes brain injury despite cerebral [O.sub.2] transport being maintained by elevated cerebral perfusion; thus sustained O2 transport does not prevent brain injury in endotoxemia. In contrast, cerebral hypoperfusion and reduced [O.sub.2] transport occur in fetuses destined to die, emphasizing the importance of sustaining [O.sub.2] transport for survival. cerebral blood flow; fetus; oxygen transport

Byline: Hiroshi Morisaki (1), Satoshi Yajima (1), Yoko Watanabe (1), Takeshi Suzuki (1), Michiko Yamamoto (1), Nobuyuki Katori (1), Saori Hashiguchi (1), Junzo Takeda (1) Keywords: Hypercapnia; Bacterial translocation; Intramucosal pH; Myeoloperoxidase Abstract: Objective Recent evidence demonstrated that hypercapnic acidosis due to lung protective strategy was not only permissive but also even therapeutic for injured lung. Since the effects of hypercapnic acidosis on extra-pulmonary organs remain to be clarified, we tested the hypothesis that hypercapnic acidosis protects gut mucosal barrier function by modulating inflammation in a rabbit model of endotoxemia. Design Prospective randomized animal study. Setting University research laboratory. Subjects Male New Zealand white rabbits. Interventions Thirty-two animals were randomly allocated into two groups: normocapnia (n = 17) and hypercapnia (n = 15). The latter group received [F.sub.I]CO.sub.2 5% under mechanical ventilation to achieve hypercapnia throughout the study periods, whereas the former with [F.sub.I]CO.sub.2 0%. Measurements and results Arterial blood gas, intramucosal pH (pHi) and portal blood flow were assessed at baseline, 2-h and 4-h infusion of lipopolysaccharide. At 4 h, ileal myeloperoxidase (MPO) activity and intestinal permeability were measured. The animals in the hypercapnia group showed apparent hypercapnic acidosis and progressive intramucosal acidosis at 4 h, accompanied by significantly lower intestinal permeability versus normocapnia group. Ileal MPO activity was comparable between the study groups. Conclusions Hypercapnic acidosis attenuates endotoxin-induced gut barrier dysfunction possibly through neutrophil-independent mechanisms. Author Affiliation: (1) Department of Anesthesiology, Keio University School of Medicine, 35 Shinanomachi, Shinjuku-ku, Tokyo, 160-8582, Japan Article History: Registration Date: 03/07/2008 Received Date: 16/11/2007 Accepted Date: 19/06/2008 Online Date: 15/07/2008 Article note: Electronic supplementary material The online version of this article (doi: 10.1007/s00134-008-1212-7) contains supplementary material, which is available to authorized users.

Melanocortin-4 receptors (MC4R) are key factors in the depression of appetite during disease. This study was designed to determine the role of agouti-related protein (AgRP) in the effect of endotoxin (lipopolysaccharide, LPS) on appetite. Sheep received an intracerebroventricular injection of either saline or AgRP (0.5 nmol/kg of BW) 1 h before intravenous injection of either saline or LPS (0.6 [micro]g/kg of BW) at time 0 and again at 4 h. Agouti-related protein prevented the reduction in feed intake due to LPS (P < 0.05). In a second experiment, AgRP gene expression was unaffected at 3 h and increased (P < 0.01) at 6 h after LPS. Immunohistochemical evidence indicated that there was an increase in the percentage of AgRP neurons with c-Fos immunoreactive nuclei 6 h after sheep were injected with LPS (P < 0.04) and a corresponding decrease in [alpha]-melanocyte-stimulating hormone neurons coexpressing c-Fos (P < 0.001). In situ hybridization provided evidence for an increase in AgRP gene expression and a decrease in proopiomelanocortin gene expression 6 h after LPS (P < 0.05). In a final experiment, physiological elevation of orexigenic agents by short-term fasting kept feed intake at the same level as controls, in spite of the presence of LPS, similar to the effects of AgRP in Exp. 1. The AgRP inhibition of the MC4R prevents appetite inhibition in response to LPS and well after LPS inhibition of feed intake, both AgRP and [alpha]-melanocyte-stimulating hormone may change in a pattern that favors appetite increases. These studies support the notion of the MC4R as a critical component of the mechanism for appetite suppression due to endotoxin. Key words: agouti-related protein, food intake, hypothalamus, melanocortin-4 receptor, [alpha]-melanocyte-stimulating hormone, sheep

Results of animal experiments suggest that consumption of refined carbohydrates (e.g. fructose) can result in small intestinal bacterial overgrowth and increased intestinal permeability, thereby contributing to the development of nonalcoholic fatty liver disease (NAFLD). Furthermore, increased plasminogen activator inhibitor (PAl)-1 has been linked to liver damage of various etiologies (e.g. alcohol, endotoxin, nonalcoholic). The aim of the present pilot study was to compare dietary factors, endotoxin, and PAl-1 concentrations between NAFLD patients and controls. We assessed the dietary intake of 12 patients with NAFLD and 6 control subjects. Plasma endotoxin and PAl-1 concentrations as well as hepatic expression of PAl-1 and toll-like receptor (TLR) 4 mRNA were determined. Despite similar total energy, fat, protein, and carbohydrate intakes, patients with NAFLD consumed significantly more fructose than controls. Endotoxin and PAl-1 plasma concentrations as well as hepatic TLR4 and PAl-1 mRNA expression of NAFLD patients were significantly higher than in contrors. The plasma PAl-1 concentration was positively correlated with the plasma endotoxin concentration (Spearman r = 0.83; P < 0.005) and hepatic TLR4 mRNA expression (Spearman r = 0.54; P < 0.05). Hepatic mRNA expression of PAl-1 was positively associated with dietary intakes of carbohydrates (Spearman r = 0.67; P < 0.01), glucose (Spearman r = 0.58; P < 0.01 ), fructose (Spearman r = 0.58; P < 0.01), and sucrose (Spearman r = 0.70; P < 0.01). In conclusion, our results suggest that dietary fructose intake, increased intestinal translocation of bacterial endotoxin, and PAl-1 may contribute to the development of NAFLD in humans.

Acute lung injury (ALI) and acute respiratory distress syndrome (ARDS) are major causes of acute respiratory failure associated with high morbidity and mortality Although ALI/ARDS pathogenesis is only partly understood, pulmonary endothelium plays a major role by regulating lung fluid balance and pulmonary edema formation. Consequently, endothelium-targeted therapies may have beneficial effects in ALI/ARDS. Recently, attention has been given to the therapeutic potential of purinergic agonists and antagonists for the treatment of cardiovascular and pulmonary diseases. Extracellular purines (adenosine, ADP, and ATP) and pyrimidines (UDP and UTP) are important signaling molecules that mediate diverse biological effects via cell-surface P2Y receptors. We previously described ATP-induced endothelial cell (EC) barrier enhancement via a complex cell signaling and hypothesized endothelial purinoreceptors activation to exert anti-inflammatory barrier-protective effects. To test this hypothesis, we used a murine model of ALI induced by intratracheal administration of endotoxin/lipopolysaccharide (LPS) and cultured pulmonary EC. The nonhydrolyzed ATP analog ATP[gamma]S (50-100 [micro] M final blood concentration) attenuated inflammatory response with decreased accumulation of cells (48% P < 0.01) and proteins (57%, P < 0.01) in bronchoalveolar lavage and reduced neutrophil infiltration and extravasation of Evans blue albumin dye into lung tissue. In cell culture model, ATP[gamma]S inhibited junctional permeability induced by LPS. These findings suggest that purinergic receptor stimulation exerts a protective role against ALI by preserving integrity of endothelial cell-cell junctions. endotoxin/lipopolysaccharide; mice; inflammation; endothelial barrier

Endotoxin [or lipopolysaccharide (LPS)] increases levels of superoxide in blood vessels and impairs vasomotor function. Angiotensin II plays an important role in the generation of superoxide in several disease states, including hypertension and heart failure. The goal of this study was to determine whether the activation of the renin-angiotensin system contributes to oxidative stress and endothelial dysfunction after endotoxin. We examined the effects of enalapril (an angiotensin-converting enzyme inhibitor) or L-158809 (an angiotensin receptor blocker) on increases of superoxide and vasomotor dysfunction in mice treated with LPS. C57BL/6 mice were treated with either enalapril (60 mg x [kg.sup.-1] x [day.sup.-1]) or L-158809 (30 mg x [kg.sup.-1] x [day.sup.-1]) for 4 days. After the third day, LPS (10-20 mg/kg) or vehicle was injected intraperitoneally, and one day later, vasomotor function of the aorta was examined in vitro. After precontraction with [PGF.sub.2[alpha]], the maximal responses to sodium nitroprusside were similar in the aorta from normal and LPS-treated mice. In contrast, the relaxation to acetylcholine was impaired after LPS (54 [+ or -] 5% at [10.sup.-5], mean [+ or -] SE) compared with vessels treated with vehicle (88 [+ or -] 1%; P < 0.05). Enalapril improved (P < 0.05) relaxation in response to acetylcholine to 81 [+ or -] 6% after LPS. L-158809 also improved relaxation in response to acetylcholine to 77 [+ or -] 4% after LPS. Superoxide (measured with lucigenin and hydroethidine) was increased (P < 0.05) in aorta after LPS, and levels were reduced (P < 0.05) following enalapril and L-158809. Thus, after LPS, enalapril and L-158809 reduce superoxide levels and improve relaxation to acetylcholine in the aorta. The findings suggest that activation of the renin-angiotensin system contributes importantly to oxidative stress and endothelial dysfunction after endotoxin. endotoxin; enalapril; L-158809; endothelial function

To identify new components that regulate the inflammatory cascade during sepsis, we characterized the functions of myeloid-related protein-8 (Mrp8, S100A8) and myeloid-related protein-14 (Mrp14, S100A9), two abundant cytoplasmic proteins of phagocytes. We now demonstrate that mice lacking Mrp8-Mrp14 complexes are protected from endotoxin-induced lethal shock and Escherichia coli-induced abdominal sepsis. Both proteins are released during activation of phagocytes, and Mrp8-Mrp14 complexes amplify the endotoxin-triggered inflammatory responses of phagocytes. Mrp8 is the active component that induces intracellular translocation of myeloid differentiation primary response protein 88 and activation of interleukin-1 receptor-associated kinase-1 and nuclear factor-[kappa]B, resulting in elevated expression of tumor necrosis factor-[alpha] (TNF-[alpha]). Using phagocytes expressing a nonfunctional Toll-like receptor 4 (TLR4), HEK293 cells transfected with TLR4, CD14 and MD2, and by surface plasmon resonance studies in vitro, we demonstrate that Mrp8 specifically interacts with the TLR4-MD2 complex, thus representing an endogenous ligand of TLR4. Therefore Mrp8-Mrp14 complexes are new inflammatory components that amplify phagocyte activation during sepsis upstream of TNF[alpha]-dependent effects., Author(s): Thomas Vogl [1]; Klaus Tenbrock [2, 3]; Stephan Ludwig [4]; Nadja Leukert [1]; Christina Ehrhardt [4]; Marieke A D van Zoelen [5]; Wolfgang Nacken [1]; Dirk Foell [2, 3]; [...]

Occupational hygiene was investigated in two Finnish combined-drum-and-tunnel composting plants, Plant A (composting sewage sludge) and Plant B (composting source-separated biowaste), in 1998-2000. The concentrations of viable mesophilic and thermophilic microbes (fungi, bacteria, and actinomycetes), the total number of microbes (viable + dead), endotoxin concentrations, and noise level were determined for each plant. In addition, dust concentrations were investigated in Plant B. In Plant A, working areas were aired before the measurements were taken. Differences in microbe concentrations between the plants were statistically significant. There were more problems with microbes in Plant B, where the working areas were not aired. Also, endotoxins were a problem in Plant B; the threshold value of 200 endotoxin units per cubic meter was exceeded in several measurements., Introduction Partly voluntarily and partly by order of the waste act, Finland is moving toward source separation of kitchen biowastes. At present, about 70 percent of Finns are sorting their [...]

Acute renal failure (ARF) in septic patients drastically increases the mortality to 50-80%. Sepsis induces several proinflammatory cytokines including tumor necrosis factor-[alpha] (TNF-[alpha]), a major pathogenetic factor in septic ARF. Pentoxifylline has several functions including downregulation of TNF-[alpha] and endothelia-dependent vascular relaxation. We hypothesized that pentoxifylline may afford renal protection during endotoxemia either by downregulating TNF-[alpha] and/or by improving endothelial function. In wild-type mice, pentoxifylline protected against the fall in glomerular filtration rate (GFR; 105.2 [+ or -] 6.6 vs. 50.2 [+ or -] 6.6 [micro]l/min, P < 0.01) at 16 h of LPS administration (2.5 mg/kg ip). This renal protective effect of pentoxifylline was associated with an inhibition of the rise in serum TNF-[alpha] (1.00 [+ or -] 0.55 vs. 7.02 [+ or -] 2.40 pg/ml, P < 0.05) and serum IL-l[beta] (31.3 [+ or -] 3.6 vs. 53.3 [+ or -] 5.9 pg/ml, P < 0.01) induced by LPS. Pentoxifylline also reversed the LPS-related increase in renal iNOS and ICAM-1 and rise in serum nitric oxide (NO). Enhanced red blood cell deformability by pentoxifylline may have increased shear rate and upregulated eNOS. Studies were therefore performed in eNOS knockout mice. The renal protection against endotoxemia with pentoxifylline was again observed as assessed by GFR (119.8 [+ or -] 18.0 vs. 44.5 [+ or -] 16.2 [micro]l/min, P < 0.05) and renal blood flow (0.86 [+ or -] 0.08 vs. 0.59 [+ or -] 0.05 ml/min, P < 0.05). Renal vascular resistance significantly decreased with the pentoxifylline (91.0 [+ or -] 5.8 vs. 178.0 [+ or -] 7.6 mmHg x [ml.sup.-1] x [min.sup.-1], P < 0.01). Thus pentoxifylline, an FDA-approved drug, protects against endotoxemia-related ARF and involves a decrease in serum TNF-[alpha], IL-1[beta], and NO as well as a decrease in renal iNOS and ICAM-1. sepsis; tumor necrosis factor

The hygiene hypothesis suggests that early life exposure to a nonhygienic environment that contains endotoxin reduces the risk of developing allergic diseases. The mechanisms underlying the hygiene hypothesis are unclear and may involve subtle immune system interactions that occur during maturation. Experimental objectives of this study were to use a novel animal model to test the hygiene hypothesis and to characterize early life immune system responses to a nonhygienic environment. Mice were reared in corn dust, a grain-processing byproduct with a high-endotoxin content and microbial products or in a low-endotoxin environment. The influence of early or later life exposure to corn dust on a subsequent allergen stimulus (ovalbumin) was assessed by bronchoalveolar lavage (BAL) cell analysis, lung histology, serum IgE, and BAL cytokine measurements. The influence of the corn dust environment on the developing pulmonary immune system was assessed by BAL cell analysis and immunostaining of lung tissue. The corn dust environment contained significantly more endotoxin (P < 0.001), and the dust exposures attenuated the cellular inflammatory response to ovalbumin in the adult mouse (P < 0.01) but did not reduce serum IgE levels or alter baseline BAL fluid proinflammatory cytokine levels. The corn dust environment did not induce significant neutrophilia in lavage fluid but significantly increased the number of antigen-presenting cells in alveolar walls early in life by ~37%. In conclusion, exposure to a nonhygienic environment did not induce significant airway neutrophilia, yet altered the population of immunologically active cells in the lung and reduced subsequent allergic inflammation. hygiene hypothesis; immune system; development; rodent doi:10.1152/ajplung.00278.2005.

Byline: Matthias Behrends (1), Jurgen Peters (1) Keywords: Sepsis; Cardiomyopathy; Myocardial function; Contractility; Calcium sensitivity; Langendorff Abstract: Objective Sepsis-evoked myocardial dysfunction is possibly due to decreased myofilament calcium sensitivity, and a calcium sensitizer may thus specifically improve contractility in sepsis by enhancing myofilament calcium sensitivity. We examined whether the calcium sensitizer levosimendan mitigates myocardial dysfunction and improves contractility in hearts isolated from endotoxin-treated guinea pigs. Design and setting Prospective, controlled, randomized animal study in a university research laboratory. Subjects Guinea pig hearts isolated 4 h (n=10) or 18 h (n=8) following E. coli LPS (4 mg/kg i.p.) and hearts from sham-treated controls (n=11 and n=6). Interventions Isolated hearts were perfused at constant aortic pressure [Krebs-Henseleit buffer, heart rate: 300/min, left ventricular (LV) diastolic pressure: 6--8 mmHg], and LV developed pressure (LVdP) and LVdP/dt were continuously assessed. Levosimendan was added to the perfusate in incremental concentrations (0.03, 0.1, 0.3 AuM). Measurements and results Endotoxin resulted in a significant decrease in LVdP by 20+-6% and 43+-8%, in +LVdP/dt by 16+-5% and 44+-7%, and in -LVdP/dt by 27+-8% and 47+-8% after 4 and 18 h, respectively. In septic hearts levosimendan increased LV function concentration-dependently by 32+-4% (LVdP), 33+-5% (+LVdP/dt), and 37+-7% (-LVdP/dt) 4 h and by 31+-6% (LVdP), 33+-6% (+LVdP/dt), and 32+-7% (-LVdP/dt) 18 h after LPS. However, levosimendan increased myocardial function similarly in control hearts. Conclusions While the calcium sensitizer levosimendan markedly improved LV contractility in hearts from both endotoxic and sham animals, it failed to specifically abolish endotoxin-evoked myocardial dysfunction. Thus, decreased calcium sensitivity either does not play a major role in endotoxin-evoked cardiomyopathy or the location of its pathomechanism differs from levosimendan's site of action. Author Affiliation: (1) Klinik fur Anasthesiologie und Intensivmedizin, Universitatsklinikum Essen, Hufelandstrasse 55, 45122, Essen, Germany Article History: Received Date: 12/12/2002 Accepted Date: 27/05/2003 Online Date: 17/07/2003

Byline: Akira Kudoh (1), Hiroshi Katagai (1), Tomoko Takazawa (1) Keywords: Ketamine; Inositol 1,4,5-triphosphate; Thromboxane A.sub.2; Intracellular calcium Abstract: Objective To investigate the effect of ketamine on endotoxin modulation of inositol 1,4,5-triphosphate (IP.sub.3) formation in cardiomyocytes. Design A prospective observational cell culture study. Setting A research laboratory in the University of Hirosaki School of Medicine. Materials Neonatal rat cardiomyocytes. Intervention We investigated bradykinin-induced IP.sub.3 production in the presence of lipopolysaccharide (LPS) and the effect of ketamine on the LPS modulation of IP.sub.3 formation. The LPS modulation of IP.sub.3 formation was measured in the presence of BM13177 (a thromboxane A.sub.2 (TXA.sub.2) receptor inhibitor) or GDP[beta]S (a GTP-binding protein inhibitor). U46619 (a TXA.sub.2 agonist)-induced IP.sub.3 production was measured in the presence of ketamine, and the ketamine modulation of U46619-induced IP.sub.3 production was measured in the presence of W7 (a Ca.sup.2+ releasing agent) and verapamil (a Ca.sup.2+ channel blocker). Results One micromole ketamine significantly attenuated the LPS-induced IP.sub.3 production from 763.8+-34.6 to 461.6+-65.1 pmol mg protein.sup.-1. Ten micromoles of BM13177 or 1 mM GDP[beta]S significantly blocked LPS modulation of bradykinin-induced IP.sub.3 production from 786.0+-33.8 to 218.6+-21.6 and 226.8+-25.4 pmol mg protein.sup.-1. One micromole of ketamine significantly decreased U46619-induced IP.sub.3 production from 857.3+-45.0 to 632.9+-64.5 pmol mg.sup.-1 protein. The ketamine inhibition of U46619-induced IP.sub.3 production was enhanced by W7 and inhibited by verapamil. Conclusion Ketamine decreased LPS-induced IP.sub.3 formation and the ketamine inhibition was associated with inhibition of the TXA.sub.2-IP.sub.3 sequence. Inhibition of TXA.sub.2 by ketamine was associated with a decrease in intracellular Ca.sup.2+. Author Affiliation: (1) Department of Anesthesiology, Hirosaki National Hospital, 1 Tominocho, Hirosaki 036-8545, Aomori, Japan Article History: Received Date: 20/12/2001 Accepted Date: 27/06/2003 Online Date: 16/08/2003 Article note: This revised version was published in August 2003 with corrections to Figures 4, 5, and 6.

In shock models, induction of endotoxin tolerance (ET) is known to have a protective effect. The present study was designed to explore if ET is effective in protecting lungs from reperfusion injury. Twelve foxhounds were used as experimental animals. After a left thoracotomy, the left hilum was clamped for 3 h, followed by 8 h of reperfusion. In the treatment group (ET, n = 6), dogs were pretreated with incremental daily endotoxin doses of up to 60 [micro]g/kg on day 6. The ischemia and reperfusion experiment was carried out on day 9. Control group animals (n = 6) were not subjected to endotoxin. Afar 8 h of observation, functional parameters of the reperfused lung of the ET and the control group were statistically different (P < 0.05) with respect to P[O.sub.2] [ET vs. control: 172.7 [+ or -] 12.9 vs. 66.1 [+ or -] 7.2 (SE) mmHg], compliance (16.0 [+ or -] 1.2 vs. 8.3 [+ or -] 1.0 ml/0.1 kPa), and the wet-to-dry ratio (9.4 [+ or -] 0.8 vs. 16.7 [+ or -] 1.2). After 3 h of warm ischemia and 8 h of reperfusion, pulmonary function and lung water content improved in the endotoxin-tolerant group. ischemia-reperfusion; acute respiratory distress syndrome; surfactant; lipopolysaccharide

A child's exposure to bacterial endotoxins in the environment may make them immune to many allergic substances later on in life. Endotoxins are bacterial proteins that can be toxic to other bacteria as well as animals and humans. In a study of 812 children, those with endotoxins in dust from their mattress were less likely to have asthma or allergy and were less likely to have an immune reaction to the endotoxin.

Byline: I.F. Tugtekin (1), P. Radermacher (1), M. Theisen (1), M. Matejovic (2), A. Stehr (3), F. Ploner (4), K. Matura (5), C. Ince (5), M. Georgieff (1), K. Trager (1) Keywords: Endotoxin Ileal-mucosal-arterial PCO2 gap Orthogonal polarization spectral imaging Lactate/pyruvate ratios Remission spectrophotometry Villus microcirculation Abstract: Objective: To investigate whether an increased ileal-mucosal-arterial PCO.sub.2 gap (IPCO.sub.2) during hyperdynamic porcine endotoxemia is associated with impaired villus microcirculation. Design: Prospective, randomized, controlled, experimental study. Setting: Animal research laboratory. Animals: Twenty-two domestic pigs. Interventions: After baseline measurements, anesthetized and ventilated pigs received continuous i.v. endotoxin (ETX, n=12) for 24 h or placebo (SHAM, n=10). Measurements and results: Before, as well as 12 and 24 h after, the start of endotoxin or saline portal venous blood flow (Q.sub.PV, ultrasound flow probe) and lactate/pyruvate ratios (L/P), the ileal-mucosal-arterial IPCO.sub.2 (fiberoptic sensor) and bowel-wall capillary hemoglobin O.sub.2 saturation (%Hb-O.sub.2-cap, remission spectrophotometry) were assessed together with intravital video records of the ileal-mucosal microcirculation (number of perfused/heterogeneously perfused/unperfused villi) using orthogonal polarization spectral imaging (CYTOSCAN A/R) via an ileostomy. At 12 and 24 h endotoxin infusion, about half of the evaluated villi were heterogeneously or unperfused which was paralleled by a progressive significant increase of the ileal-mucosal-arterial IPCO.sub.2 and portal venous L/P ratios, whereas Q.sub.PV as well as both the mean %Hb-O.sub.2-cap and the %Hb-O.sub.2-cap frequency distributions remained unchanged. By contrast, in the SHAM-group, mucosal microcirculation was well-preserved, and none of the other parameters were influenced. Conclusions: We conclude that an increased ileal-mucosal-arterial IPCO.sub.2 during porcine endotoxemia is related to impaired villus microcirculation. A putative contribution of disturbed cellular oxygen utilization resulting from 'cytopathic hypoxia' may also assume importance. Author Affiliation: (1) Sektion Anasthesiologische Pathophysiologie und Verfahrensentwicklung, Universitatsklinik fur Anasthesiologie, Parkstrasse 11, 89075, Ulm, Germany (2) I. Interni Kliniky, Karlova Universita, Plzen, Czech Republic (3) Klinik und Poliklinik fur Chirurgie, Universitatsklinikum, Regensburg, Germany (4) Abteilung Anasthesiologie und Reanimation, Bezirkskrankenhaus, Sterzing, Italy (5) Afdeling Experimentele Anaesthesiologie, Academisch Medisch Centrum, Amsterdam, The Netherlands Article History: Received Date: 26/07/2000 Accepted Date: 29/12/2000 Article note: Final revision received: 7 December 2000 Electronic Publication

Byline: C. Venet (1), F. Zeni (1), A. Viallon (1), A. Ross (2), P. Pain (1), P. Gery (1), D. Page (1), R. Vermesch (1), M. Bertrand (1), F. Rancon (1), J. C. Bertrand (1) Keywords: Key words Endotoxaemia; Severe sepsis; Septic shock; Clinical study; Outcome; Bacteraemia; Gram-negative bacteria infection Abstract: Objective: To examine the incidence and the bacteriological and clinical significance of endotoxaemia in ICU patients with severe sepsis or septic shock. Design: Prospective review. Setting: A 15-bed general ICU in a university hospital. Patients: One hundred sixteen patients hospitalised in our ICU fulfilling Bone's criteria for severe sepsis or septic shock and with an available early endotoxin assay (chromogenic limulus assay). Interventions: None. Measurements and results: The clinical characteristics of the population were: age 63.6 +- 11.4 years SAPS II: 45.4 +- 15.6 mechanical ventilation: 72.4 % septic shock: 51.7 % (n = 60) bacteraemia: 28.4 % (n = 33) gram-negative bacteria (GNB) infection 47.4 % (n = 55) ICU mortality: 39.6 % (n = 46). Detectable endotoxin occurred in 61 patients (51.2 % mean level: 310 +- 810 pg/ml). There was no relationship between detectable endotoxin and severity of infection at the moment of the assay. Endotoxaemia was associated with a higher incidence of bacteraemia (39.3 % vs 16.3 % p = 0.01). There was a trend (p = 0.09) towards an association between positive endotoxin and gram-negative bacteraemia or GNB infection but this was non-significant. This relationship became significant only in the case of bacteraemia associated with GNB infection irrespective of the site of infection. Conclusion: Early detection of endotoxaemia appeared to be associated with GNB infection only in cases of bacteraemic GNB infection. Early endotoxaemia correlated neither to occurrence of organ dysfunction nor mortality in patients with severe sepsis or septic shock. This study suggests that the use of endotoxaemia as a diagnostic or a prognostic marker in daily practice remains difficult. Author Affiliation: (1) Intensive Care Unit, Hopital Bellevue, Boulevard Pasteur, F-42055 Saint-Etienne Cedex 2, France, FR (2) Department of Microbiology, Hopital Nord, F-42055 Saint-Etienne Cedex 2, France, FR Article note: Received: 28 September 1999 Final revision received: 31 January 2000 Accepted: 1 February 2000

Byline: F. Strutz (1), G. Heller (1), K. Krasemann (1), B. Krone (2), G. A. Muller (1) Keywords: Key words Sepsis syndrome; Medical intensive care; Endotoxin; Endotoxin core antibodies; Sepsis score; Prognostic factors Abstract: Objectives: To assess the prognostic value of determining anti-endotoxin core antibodies (EndoCab) immunoglobulin (Ig)G and IgM in medical patients with sepsis syndrome in order to identify patient subgroups that may profit from endotoxin-neutralizing therapy. The findings were correlated with clinical outcome, endotoxin levels and sepsis score. Design: Cohort study with a follow-up period of 30 days. Setting: Medical intensive care units (2) of a university hospital. Patients and methods: Twenty-nine patients who fulfilled the criteria of sepsis syndrome and did not present with septic shock or had not been treated with antibiotics for more than 3 days were included in the study. Twenty-one intensive care patients without infections served as controls for antibody concentrations. Interventions: Blood samples were obtained from indwelling arterial catheters or direct venipuncture on admission and daily thereafter until transfer to a regular unit. Sepsis scores were determined daily. Results: The mortality rate at 30 days was 44.8 % (13 out of 29). Sepsis patients had significantly lower initial EndoCab IgM and IgG concentrations than controls. Initial EndoCab IgG concentrations were significantly lower in non-survivors of sepsis syndrome but not in survivors compared to controls (median concentrations 51.5 vs 110.1 vs 245.4 MU/ml). EndoCab IgM and IgG were lower in non-survivors compared to survivors, though that difference failed to reach significance (p = 0.11 in both cases). Depletion of initial EndoCab IgM concentrations (defined as a value below the 10th percentile of a control population) was present in 15 patients, 9 of whom died, and depletion of IgG in five patients, four of whom died. EndoCab IgM and IgG concentrations rose concordantly in survivors and non-survivors in the course of the disease. Endotoxin levels were significantly higher in non-survivors compared to controls but not in survivors. A sepsis score of 21 and higher was associated with 90.9 % mortality (specificity 93.8 %, sensitivity 76.9 %). Conclusions: Decreased EndoCab IgG concentrations are associated with increased mortality in medical patients with sepsis syndrome. The measurement of initial anti-endotoxin antibodies may provide a useful tool to identify septic patients who profit potentially from endotoxin neutralizing therapy, however considerable overlap of antibody concentrations warrants additional parameters. The sepsis score is easy to determine and useful in the evaluation of medical patients with sepsis. Author Affiliation: (1) Department of Nephrology and Rheumatology, Georg-August-University Medical Center, Robert-Koch-Str. 40, D-37 075 Gottingen, Germany e-mail: fstrutz@gwdg.de Tel. + 49 (551) 39 63 31 Fax + 49 (5 51) 39 89 06, DE (2) Department of Microbiology, Georg-August-University Medical Center, Robert-Koch-Str. 40, D-37 075 Gottingen, Germany, DE Article note: Received: 4 September 1998 Final revision received: 28 December 1998 Accepted: 15 February 1999

Byline: S. Schroeder (1), J. Bischoff (1), L. E. Lehmann (1), R. Hering (1), T. von Spiegel (1), C. Putensen (1), A. Hoeft (1), F. Stuber (1) Keywords: Key words Heat shock protein 70; Peripheral blood mononuclear cells; HSP70 enzyme-linked immunosorbent assay; Lipopolysaccharide; Severe sepsis; Stress protein Abstract: Objective: To investigate the ex vivo endotoxin-inducible heat shock protein 70 (HSP70) expression in the peripheral blood mononuclear cells (PBMC) of patients with severe sepsis in order to assess the capacity of this potentially protective response during systemic inflammation. Design: Prospective observational study in consecutive patients with severe sepsis and healthy blood donors. Setting: Surgical intensive care unit in a university hospital. Patients and participants: Eleven patients with the diagnosis of severe sepsis, one patient who had recovered from severe sepsis and 13 healthy blood donors. Interventions: None. Measurements and results: We studied the inducibility of HSP70 expression in the PBMC of patients with severe sepsis and healthy blood donors ex vivo. Human whole blood was incubated with variable lipopolysaccharide (LPS from Salmonella minnesota Re 595) concentrations (0 0.1 10 100 ng/ml) for different periods of time (0.5 2 4 10 h). The PBMC were separated by Ficoll density gradient and then disrupted by hypotonic lysis. HSP70 was measured by means of enzyme-linked immunosorbent assay (ELISA). We found a LPS dose- and time-dependent inhibition of ex vivo HSP70 expression in the PBMC of both patients with severe sepsis and healthy individuals. However, the levels of HSP70 expression in patients were significantly lower compared to those of healthy individuals at all LPS concentrations and incubation times. On average, HSP70 expression in the PBMC of healthy controls was 2.8 (range 1.2--3.9) times higher than in patients. HSP70 expression was inducible by thermal heat shock in the PBMC of both patients and healthy individuals. Conclusions: Endotoxin inhibits HSP70 expression in PBMC ex vivo. In vivo, the suppression of HSP70 expression induced by endotoxin and high levels of proinflammatory cytokines may contribute to the cellular dysfunction of immunocompetent cells concerning antigen presentation, phagocytosis and antibody production associated with decreased resistance to infectious insults during severe sepsis. Author Affiliation: (1) Klinik und Poliklinik fur Anasthesiologie und Spezielle Intensivmedizin, Rheinische Friedrich-Wilhelms-Universitat Bonn, Sigmund-Freud-Strasse 25, D-53 105 Bonn, Germany e-mail: schroed@mailer.meb.uni-bonn.de Tel. + 49 (228) 287-6018 Fax + 49 (228) 287--5157, DE Article note: Received: 9 July 1998 Final revision received: 12 October 1998 Accepted: 29 October 1998

BACKGROUND: Although occupational exposures contribute to a significant proportion of obstructive lung disease, the phenotype of obstructive lung disease associated with work-related organic dust exposure independent of smoking remains poorly defined. OBJECTIVE: We identified the relative contributions of smoking and occupational endotoxin exposure to parenchymal and airway remodeling as defined by quantitative computed tomography (CT). METHODS: The Shanghai Textile Worker Study is a longitudinal study of endotoxin-exposed cotton workers and endotoxin-unexposed silk workers that was initiated in 1981. Spirometry, occupational endotoxin exposure, and smoking habits were assessed at 5-year intervals. High-resolution computed tomography (CT) was performed in 464 retired workers in 2011, along with quantitative lung densitometric and airway analysis. RESULTS: Significant differences in all CT measures were noted across exposure groups. Occupational endotoxin exposure was associated with a decrease (-1.3%) in percent emphysema ([LAA.sub.I-950]), a 3.3-Hounsfield unit increase in 15th percentile density, an 18.1-g increase in lung mass, and a 2.3% increase in wall area percent. Current but not former smoking was associated with a similar CT phenotype. Changes in [LAA.sub.I-950] were highly correlated with 15th percentile density (correlation -1.0). Lung mass was the only measure associated with forced expiratory volume in 1 sec ([FEV.sub.1]) decline, with each 10-g increase in lung mass associated with an additional loss (-6.1 mL) of [FEV.sub.1] (p = 0.001) between 1981 and 2011. CONCLUSIONS: There are many similarities between the effects of occupational endotoxin exposure and those of tobacco smoke exposure on lung parenchyma and airway remodeling. The effects of occupational endotoxin exposure appear to persist even after the cessation of exposure. [LAA.sub.I-950] may not be a reliable indicator of emphysema in subjects without spirometric impairment. Lung mass is a CT-based biomarker of accelerated lung function decline. http://dx.doi.org/10.1289/EHP195, Introduction Chronic obstructive pulmonary disease (COPD) is the fifth leading cause of death in developed countries [Global Burden of Disease (GBD) 2013 Mortality and Causes of Death Collaborators 2015]. Recent [...]

Byline: W. Schmidt (1), A. Walther (1), E. Martin (1), H. Schmidt (1), M. M. Gebhard (2) Keywords: Endotoxemia; Leukocyte adherence; Microcirculation; N-acetylcysteine; Rat mesentery; Vascular permeability Abstract: Objectives To determine the influence of N-acetylcysteine (NAC) in a treatment model, its effects on endotoxin-induced leukocyte-endothelial cell adhesion, vascular leakage, and venular micro-hemodynamics in postcapillary venules of rat mesentery. Design Prospective, randomized, controlled, experimental study. Setting Animal research laboratory. Subjects 40 male Wistar rats. Interventions The rats randomly received one of four treatments: infusion of saline (SAL) or Escherichia coli lipopolysaccharides (LPS) followed by treatment with saline (SAL) or NAC (150 mg * kg.sup.- body weight) 30 min after induction of endotoxemia. Measurements and main results Leukocyte adherence, red blood cell velocity, and vessel diameters in postcapillary venules of rat mesentery were evaluated every 30 min over a period of 120 min using in vivo videomicroscopy. Vascular permeability was determined by measuring the extravasation of fluorescence-labeled albumin. Venular wall shear rate was calculated from red cell velocity, and vessel diameter. NAC in rats without endotoxemia (SAL + NAC group) compared to the control group (SAL + SAL) did not change microcirculatory parameters in postcapillary venules of rat mesentery. In both LPS-treated groups (LPS + SAL and LPS + NAC), leukocyte adherence increased after just 30 min. NAC treatment prevented a further increase in leukocyte adherence and attenuated the extravasation of fluorescence-labeled albumin during endotoxemia. Venular diameters remained unchanged, while erythrocyte velocity decreased in the LPS + SAL group. This led to a lower venular wall shear rate in this group. Conclusions Treatment with NAC attenuates endotoxin-induced leukocyte adherence and macromole-cular leakage in postcapillary venules of rat mesentery, showing that NAC is also effective after the onset of endotoxemia. Author Affiliation: (1) Department of Anesthesiology, University of Heidelberg, Im Neuenheimer Feld 110, D-69120, Heidelberg, Germany (2) Department of Experimental Surgery, University of Heidelberg, D-69120, Heidelberg, Germany Article History: Registration Date: 23/03/2009 Received Date: 22/12/1997 Accepted Date: 08/06/1998 Article note: Supported by an Institutional Research Fund of the Department of Anesthesiology, University of Heidelberg, Germany

Byline: B. S. Loeffler (1), W. A. Arden (1), R. R. Fiscus (1), L.-Y. Lee (1) Keywords: Key words: Tachykinins--Histamine--Airway inflammation--Bronchopulmonary C-fibers--Lipopolysaccharide--Guinea pigs. Abstract: Inhaled endotoxin, lipopolysaccharide (LPS), has been shown to result in bronchial hyperresponsiveness (BHR) to endogenous bronchoconstrictive mediators such as histamine. To determine the role of sensory neuropeptides released from bronchopulmonary C-fibers in LPS-induced BHR, 24 guinea pigs were allocated randomly to the following four groups. Animals in Groups I and IV were challenged with intratracheal instillation of 100 ul of saline vehicle, and those in Groups II and III with 1 mg of LPS (Escherichia coli, 0111:B4) in 100 ul of saline. Groups III and IV also received a high dose capsaicin (HDC) treatment to deplete tachykinins from C-fibers 1--2 weeks prior to the experiment. Animals were anesthetized and paralyzed, and total lung resistance (R.sub.L) and compliance (C.sub.dyn) were measured continuously during the experiment. Dose responses of R.sub.L and C.sub.dyn to histamine (0--8 ug/kg, intravenously) and capsaicin (0--1.6 ug/kg, intravenously), a specific C-fiber stimulant, were obtained prior to and at 1, 2, and 3 h following LPS/saline vehicle challenge. At 2 h after LPS, IR.sub.L caused by histamine (8 ug/kg) was significantly higher in Group II (1.145%) than that in Group I (280% p &lt 0.05) similarly, IR.sub.L caused by capsaicin (1.6 ug/kg) was also increased after LPS (Group I, 107% Group II, 267% p &lt 0.05). Although HDC treatment completely abolished the bronchomotor response to capsaicin in both Groups III and IV, it enhanced the LPS-induced BHR to histamine (8 ug/kg Group III, 1.834% p &lt 0.05). In conclusion, these results suggest that the role of tachykinins in LPS-induced BHR may be dependent upon the type and the route of administration of the bronchoactive substance studied. Author Affiliation: (1) Departments of Physiology and Surgery, University of Kentucky, Lexington, Kentucky 40536-0084, US Article note: Accepted for publication: 13 December 1996