Zeptomole per milliliter detection and quantification of edema factor in plasma by LC-MS/MS yields insights into toxemia and the progression of inhalation anthrax.

Inhalation of Bacillus anthracis spores can cause a rapidly progressing fatal infection. B. anthracis secretes three protein toxins: lethal factor (LF), edema factor (EF), and protective antigen (PA). EF and LF may circulate as free or PA-bound forms. Both free EF (EF) and PA-bound-EF (ETx) have adenylyl cyclase activity converting ATP to cAMP. We developed an adenylyl cyclase activity-based method for detecting and quantifying total EF (EF+ETx) in plasma. The three-step method includes magnetic immunocapture with monoclonal antibodies, reaction with ATP generating cAMP, and quantification of cAMP by isotope-dilution HPLC-MS/MS. Total EF was quantified from 5PL regression of cAMP vs ETx concentration. The detection limit was 20 fg/mL (225 zeptomoles/mL for the 89 kDa protein). Relative standard deviations for controls with 0.3, 6.0, and 90 pg/mL were 11.7-16.6% with 91.2-99.5% accuracy. The method demonstrated 100% specificity in 238 human serum/plasma samples collected from unexposed healthy individuals, and 100% sensitivity in samples from 3 human and 5 rhesus macaques with inhalation anthrax. Analysis of EF in the rhesus macaques showed that it was detected earlier post-exposure than B. anthracis by culture and PCR. Similar to LF, the kinetics of EF over the course of infection were triphasic, with an initial rise (phase-1), decline (phase-2), and final rapid rise (phase-3). EF levels were ~ 2-4 orders of magnitude lower than LF during phase-1 and phase-2 and only ~ 6-fold lower at death/euthanasia. Analysis of EF improves early diagnosis and adds to our understanding of anthrax toxemia throughout infection. The LF/EF ratio may also indicate the stage of infection and need for advanced treatments.

[METABOLIC INTOXICATION IN THERMIC TRAUMA].

In 76 injured persons with deep and superficial burns, having area from 3 to 65% of the total body surface and ageing 5-16 yrs old, there was investigated the impact of early surgical treatment on the metabolic intoxication severity in accordance to content of the oxidatively modified proteins carbonyl groups in the blood serum, and of a ceruloplasmin, what was considered as integral express-index of the organism antioxidant system state. Changes of these indices in ambustial disease of middle severity have witnessed a sufficiently compensated reaction of organism: of severe and extremely severe one--there were noted a deficiency of the organism antioxidant defense; and in stages of toxemia and septicotoxemia--attrition of the organism oxidant reserves and danger of the septic complications occurrence. Conduction of early surgical intervention have guaranteed maintenance of a ceruloplasmin content in stages of toxemia and septicotoxemia on the level of healthy persons, relief of the ambustial disease course, absence of critical metabolic intoxication and carbonyl stress, reduction of the septic complications rate in 1.5 times.

Botulism toxemia following laparoscopic appendectomy.

We describe a case of botulism infection in a patient who had undergone laparoscopic appendectomy, an occurrence not previously described in the literature. This case exemplifies the need for coordination between clinical and public health personnel to ensure the immediate recognition and treatment of suspected botulism cases.

Distinct physiologic and inflammatory responses elicited in baboons after challenge with Shiga toxin type 1 or 2 from enterohemorrhagic Escherichia coli.

Shiga toxin-producing Escherichia coli is a principal source of regional outbreaks of bloody diarrhea and hemolytic-uremic syndrome in the United States and worldwide. Primary bacterial virulence factors are Shiga toxin types 1 and 2 (Stx1 and Stx2), and we performed parallel analyses of the pathophysiologies elicited by the toxins in nonhuman primate models to identify shared and unique consequences of the toxemias. After a single intravenous challenge with purified Stx1 or Stx2, baboons (Papio) developed thrombocytopenia, anemia, and acute renal failure with loss of glomerular function, in a dose-dependent manner. Differences in the timing and magnitude of physiologic responses were observed between the toxins. The animals were more sensitive to Stx2, with mortality at lower doses, but Stx2-induced renal injury and mortality were delayed 2 to 3 days compared to those after Stx1 challenge. Multiplex analyses of plasma inflammatory cytokines revealed similarities (macrophage chemoattractant protein 1 [MCP-1] and tumor necrosis factor alpha [TNF-alpha]) and differences (interleukin-6 [IL-6] and granulocyte colony-stimulating factor [G-CSF]) elicited by the toxins with respect to the mediator induced and timing of the responses. Neither toxin induced detectable levels of plasma TNF-alpha. To our knowledge, this is the first time that the in vivo consequences of the toxins have been compared in a parallel and reproducible manner in nonhuman primates, and the data show similarities to patient observations. The availability of experimental nonhuman primate models for Stx toxemias provides a reproducible platform for testing antitoxin compounds and immunotherapeutics with outcome criteria that have clinical meaning.

An outbreak of enterotoxaemia at livestock farm during subtropical summer.

Present investigations were carried out on 10 dead animals including eight in lambs, one in goat kid and one in calf during subtropical summer at a local farm. The weather was hot and humid with rain occurring during the period. The history suggests an association of weather and concentrate/lush green diet/fodder with occurrence of the disease. The most consistent clinical signs reported were no interest in feeding, herding in a corner with head down, diarrhea of low degree and temperature around 102 degrees F. At postmortem examination, the most consistent findings were swollen soft kidneys, hydropericardium, congested and edematous lungs, congested liver, myocardial hemorrhages and ballooning of intestines. The histopathological examination revealed the most striking changes in kidney of vacuolation in renal tubular epithelial cells and increased Bowman's space in the glomeruli. The histopathological examination of liver revealed congestion. Lungs revealed congestion and edema. The urine from urinary bladder collected showed high glucose. The deaths in these animals were probably due to enterotoxaemia type D.

NF-kappaB regulation of endothelial cell function during LPS-induced toxemia and cancer.

The transcription factor NF-kappaB is an important regulator of homeostatic growth and inflammation. Although gene-targeting studies have revealed important roles for NF-kappaB, they have been complicated by component redundancy and lethal phenotypes. To examine the role of NF-kappaB in endothelial tissues, Tie2 promoter/enhancer-IkappaBalpha(S32A/S36A) transgenic mice were generated. These mice grew normally but exhibited enhanced sensitivity to LPS-induced toxemia, notable for an increase in vascular permeability and apoptosis. Moreover, B16-BL6 tumors grew significantly more aggressively in transgenic mice, underscoring a new role for NF-kappaB in the homeostatic response to cancer. Tumor vasculature in transgenic mice was extensive and disorganized. This correlated with a marked loss in tight junction formation and suggests that NF-kappaB plays an important role in the maintenance of vascular integrity and response to stress.

Histomorphometric study of placental villi vascular volume in toxemia and diabetes.

The quantitative changes in the vascular tree in placentas from pregnancies complicated by diabetes mellitus and preeclampsia (PE) are not well defined. The purpose of this study was to quantify placental villi cross-sectional area of capillaries assessed by a computerized morphometry system in pregnancies complicated by PE (n = 23), well-controlled pregestational diabetes mellitus (PGDM; n = 10), and healthy controls (n = 13). Our aims were to test whether villous capillarization volume was changed in PE without intrauterine growth restriction or PGDM compared with the control group and to study these effects in 3 different areas of the placenta. Examination of placentas in women with PGDM and PE revealed limited pathological changes on light microscopic examination. However, the morphometric analysis revealed a more than 5-fold decrease of villous vascular volume in PGDM compared with controls (P = .003) and a 1.6-fold decrease in the PE group that did not reach statistical significance. These findings show quantitative changes in the villous vascular tree in PGDM that are not detectable by conventional light microscopy and suggest that morphometric analysis of the capillary tree may have diagnostic importance in this entity. The findings differ significantly from those previously reported in pregestational diabetes and do not differ significantly from those reported in PE without intrauterine growth restriction.

Simvastatin inhibits inflammatory properties of Staphylococcus aureus alpha-toxin.

BACKGROUND: Simvastatin, a 3-hydroxy-methylglutaryl coenzyme A reductase inhibitor, has been shown to lower serum cholesterol levels in clinical use. Moreover, statins exert beneficial effects in vascular diseases by inhibition of leukocyte rolling, adherence, and transmigration. The aim of this study was to determine if pretreatment with simvastatin attenuates Staphylococcus aureus alpha-toxin-induced increase in leukocyte-endothelial interactions during exotoxemia. METHODS AND RESULTS: The effects of simvastatin on leukocyte-endothelial cell interactions were observed by intravital microscopy in the rat mesenteric microcirculation. Simvastatin (50 or 100 microg/kg) was administered 18 hours before the study. Activation of microcirculation was induced by bolus administration of 40 microg/kg S aureus alpha-toxin. Exotoxemia resulted in a significant and time-dependent increase in leukocyte rolling, adherence, and transmigration of leukocytes as well as P-selectin expression on the intestinal vascular endothelium. Pretreatment with simvastatin significantly inhibited exotoxin-induced leukocyte rolling from 71+/-10 to 14+/-4.7 cells/min (P<0.01) and adherence from 14+/-3.5 to 0.4+/-0.2 cells (P<0.01). In addition, simvastatin pretreatment significantly inhibited transmigration of leukocytes from 10.5+/-1.2 to 4.2+/-0.9 (P<0.05) cells. Immunohistochemical detection of endothelial cell adhesion molecule P-selectin showed a 50% decrease in endothelial cell surface expression after simvastatin treatment. Furthermore, simvastatin treatment resulted in enhanced expression of endothelial cell NO synthase III in the intestinal microcirculation. CONCLUSIONS: These results demonstrate that simvastatin interferes with exotoxin-induced leukocyte-endothelial cell interactions, which may be relevant in various infectious diseases. Statin treatment may offer a new therapeutic strategy for these clinical conditions.

[Staphylococcal and streptococcal pediatric toxic syndrome from 1998 to 2000. Data from the National Center for Staphylococcal Toxemia]. / Les syndromes toxiques staphylococciques et streptococciques pédiatriques de 1998 à 2000. Données du Centre national de référence des toxémies à staphylocoques.

The clinical and microbial settings of staphylococcal and streptococcal toxemia in pediatric patients were investigated by the French National Reference Center for Staphylococcal Toxemia. From 1998 to 2000, the number of cases was low in regard to the usual putative incidence of these toxemia; this low incidence was probably linked to the passive collection of cases. The most significant finding was the evidence of skin infections as the source of the majorities of staphylococcal toxic shock syndrome and staphylococcal scarlet fever as described for streptococcal toxic shock syndrome or nosocomial suppurative infections. Moreover, most of scalded skin syndrome were from pediatric patients and were exceptional in adults. For other syndromes, no significant original findings were observed.

Pathomorphological characteristics of experimental toxemia induced by thermostable Yersinia pseudotuberculosis toxin.

Pathogenic properties of thermostable toxin responsible for pathogenicity of Yersinia pseudotuberculosis were experimentally studied. The toxin exerted a pronounced polyorgan cytopathogenic effect with predominating degenerative destructive changes and membranolytic effect on cell ultrastructure of parenchymatous organs. The toxin is believed to be directly involved in the development of typical pathomorphological picture of pseudotuberculosis, which confirms its pathogenetic role.

Lidocaine attenuates the hypotensive and inflammatory responses to endotoxemia in rabbits.

OBJECTIVE: To assess the effects of lidocaine on the hemodynamic and inflammatory responses to Escherichia coli endotoxemia in rabbits. DESIGN: Prospective, randomized, controlled experimental study. SETTING: University laboratory. SUBJECTS: Twenty-seven female Japanese rabbits, anesthetized with urethane and ventilated mechanically. INTERVENTIONS: Animals were randomly assigned to one of three groups: a) endotoxemic control group (n = 9), receiving intravenous Escherichia coli endotoxin (0.5 mg/kg bolus) via the mesenteric vein; b) laparotomy control group (n = 9), treated identically to the endotoxemic control group, except for substitution of 0.9% saline for endotoxin; and c) lidocaine-treated group (n = 9), treated identically to the endotoxemic controls and additionally, intravenous lidocaine (3 mg/kg bolus, followed by infusion at 2 mg/kg/hr) was administered immediately after endotoxin MEASUREMENTS AND MAIN RESULTS: We compared hemodynamics, blood gases, and microscopic findings of lung tissue obtained at necropsy in each group. Laparotomy alone had a minimal effect on the parameters and findings. Endotoxin injection decreased mean systolic arterial pressure from 135 +/- 6 (SD) to 95 +/- 25 mm Hg (p < .05) and increased the mean base deficit from -1.2 +/- 1.8 to -14.4 +/- 4.2 mmol/L (p < .05), and caused the infiltration of neutrophils into the lungs. Lidocaine administration abolished the hypotension and attenuated the increase the base deficit to -9.5 +/- 2.1 mmol/L (p < .05) and the cellular infiltration in comparison with endotoxemic controls. CONCLUSIONS: Lidocaine attenuated the hemodynamic and inflammatory responses to endotoxemia in rabbits. Findings suggest that lidocaine administration may prevent the development of hypotension and metabolic acidosis during endotoxemia.

Attenuation of hepatic neutrophil sequestration by anti-CINC antibody in endotoxic rats.

Cytokine-induced neutrophil chemoattractant (CINC) is a member of the chemokine alpha sub-family. It is induced in rats by tumor necrosis factor-alpha (TNF-alpha), interleukin-1, and lipopolysaccharide and is implicated in neutrophil infiltration in response to inflammatory stimuli. We tested the hypothesis that pretreatment with anti-CINC antibody or by cobra venom factor attenuates hepatic neutrophil accumulation induced by a 90 min infusion of Escherichia coli endotoxin. Changes in the expression of CD11b/c and CD18 and in plasma TNF-alpha levels were also investigated. Cultured hepatocytes and Kupffer cells of endotoxic rats produced significantly more CINC than those of saline-infused controls. CINC generation by Kupffer cells was much lower than generation by hepatocytes. Pretreatment with anti-CINC antibody or cobra venom factor significantly reduced hepatic neutrophil sequestration, but did not affect the up-regulation of CD11b/c and CD18 expression on liver-sequestered neutrophils or plasma TNF-alpha levels. We conclude that CINC-mediated hepatic neutrophil accumulation may not be necessarily associated with up-regulation of neutrophil adhesion molecules or elevated circulating TNF-alpha levels. Attenuation of hepatic neutrophil sequestration by anti-CINC antibody is likely based on blocking of the chemotactic activity of CINC and thus diminishing the chemotactic gradient established in the liver.

Effect of parenteral antioxidants on adrenal pathobiology and leukocytes in hyperammonaemic toxaemia.

Infestation of sheep by L. cuprina larvae produces extensive skin wounds, severe dermatitis, hyperammonaemia and stress with adrenal necrosis and haemmorhage. In infested sheep, intramuscular (im) injections of Dl-Alpha tocopherol induced wool shedding and Desferrioxamine im prevented declines in white blood cells (WBC). In further trials, daily im injections of sodium ascorbate with Dl-alpha tocopherol, desferrioxamine and oral butylated-hydroxyanisole prevented adrenal damage and induced adrenocortical hypertrophy of the zona fasciculata. The treatment boosted the levels of mature and juvenile neutrophils, and blood glucose. Increases in toxic ammonia levels were correlated with increased toxic and band neutrophils, and globulin levels in treated sheep and toxic neutrophils in non-treated sheep. Decreases in serum zinc were correlated with declining lymphocytes and globulin levels. The results suggested that antioxidants protect and enhance adrenal activation in hyperammonaemic toxaemia. The changes in WBC, globulins and glucose were consistent with protected adrenocortical activation.

Endogenous tumor necrosis factor (TNF) production and modification of pathological lesions in experimental Escherichia coli endotoxemia of piglets.

We examined the kinetics of tumor necrosis factor (TNF) production induced by Escherichia coli lipopolysaccharide (LPS) in relation to LPS tolerance and endotoxemic lesions of piglets. The plasma of piglets demonstrated cytotoxicity to TNF-sensitive L929 cells between 0.5 and 4 h after inoculation with 200 micrograms kg-1 of LPS. This cytotoxicity was neutralized by anti-bovine TNF serum. These piglets had disseminated intravascular coagulation (DIC) and meningoencephalitis. However, if piglets were first treated with three doses of 40 micrograms kg-1 of LPS, both TNF production and the occurrence of DIC were inhibited when 200 micrograms kg-1 of LPS was inoculated into these piglets. Repetitive inoculation with increasing doses of LPS induced fibrinoid vasculitis, meningoencephalitis and pneumonitis, while hemorrhage was minimal. A very low amount of TNF activity was detected from most of the samples of a piglet after repeated LPS inoculation. These results suggested that severity of the hemorrhagic and thrombotic lesions might relate to the amount of endogenous TNF activity, and that LPS tolerance might relate to inhibition of TNF production.

Increased neutrophil respiratory burst in bcr-null mutants.

Philadelphia (Ph)-positive leukemias invariably contain a chromosomal translocation fusing BCR to ABL. The BCR-ABL protein is responsible for leukemogenesis. Here we show that exposure of bcr-null mutant mice to gram-negative endotoxin led to severe septic shock and increased tissue injury by neutrophils. Neutrophils of bcr (-/-) mice showed a pronounced increase in reactive oxygen metabolite production upon activation and were more sensitive to priming stimuli. Activated (-/-) neutrophils displayed a 3-fold increased p21rac2 membrane translocation compared with (+/+) neutrophils. These results connect Bcr in vivo with the regulation of Rac-mediated superoxide production by the NADPH-oxidase system of leukocytes and suggest a link between Bcr function and the cell type affected in Ph-positive leukemia.

Acute febrile diarrhoea in horses: 86 cases (1986-1991).

Eighty-six horses presented for examination at the Rural Veterinary Centre between January 1986 to December 1991 with acute diarrhoea. The average age of affected horses was 3.2 +/- 0.2 years (mean +/- SE), with 69% three years or younger. Sixty-one horses were male (36 stallions, 25 geldings) and 83 horses were Thoroughbreds (47) or Standardbreds (36). Sixty-six horses were undergoing routine training at the time of onset of diarrhoea. Eight horses were afflicted with a non-specific illness within one to five days before the onset of diarrhoea, whereas eight horses developed diarrhoea during or within 48 h of discontinuation of antimicrobial therapy. Three horses developed the diarrhoea within 24 h of road transportation. Clinically, the disorder was characterised by a fever, sudden onset of profuse diarrhoea, clinical evidence of dehydration (estimated to be 5 to 12% of body weight at the time of admission) and shock. Degenerative leucopaenia, hyponatraemia, hypochloraemia, hyperkalaemia, hyperglycaemia and azotaemia were characteristic laboratory findings. Laminitis was a sequel in about 30% of cases. The cause of diarrhoea remained undetermined in most cases. Salmonellas were isolated from faecal or tissue samples in only two cases. Similarly, there was no evidence of seroconversion to Erhlichia risticii in 17 cases. Sixty-two of the horses survived the acute phase of the disease in response to supportive care. In horses that did not survive, necropsies were performed and revealed sanguineous or turbid peritoneal fluid. The colonic and caecal walls were oedematous and thickened with serosal congestion and discolouration of these organs evident grossly.(ABSTRACT TRUNCATED AT 250 WORDS)

Role of neutrophils and platelets in the pathogenesis of focal hepatocellular necrosis in endotoxaemia.

To clarify whether neutrophils and platelets are implicated in the pathogenesis of focal hepatocellular necrosis in endotoxaemia, we examined the relationship between the changes in neutrophils and platelets in peripheral blood and the degree of focal hepatocellular necrosis and serum transaminase activity in rats after endotoxin injection. The number of neutrophils in the peripheral blood decreased rapidly during the first hour after endotoxin injection and then increased. This initial decrease might be caused by the adhesion of neutrophils to pulmonary capillary walls, and the subsequent increase might be caused by granulocyte colony-stimulating factor mediated by endotoxin. However, there was no relationship between the degree of focal hepatocellular necrosis and the number of neutrophils sticking to the walls of hepatic sinusoids or the changes in the neutrophil count in the peripheral blood. The number of platelets in the peripheral blood decreased rapidly after endotoxin injection. There was a statistically significant relationship between the number of platelets in the peripheral blood and the level of serum transaminase activity: the fewer the platelets, the more severe was focal hepatocellular necrosis. The present study suggests that rapid and extensive consumption of platelets, rather than neutrophils sticking to the sinusoidal walls, is involved in the pathogenesis of focal hepatocellular necrosis in endotoxaemia.

Endotoxemia and intestinal mucosal dysfunction after the relief of obstructive jaundice by internal and external drainage in rats.

We studied the effects of external and internal biliary drainage on the development of endotoxemia in a rat model of obstructive jaundice. Male Donryu rats were allocated to four groups: sham operation, common hepatic bile duct ligation (BDL), internal or external biliary drainage after BDL, and biliary drainage after BDL with oral endotoxin administration. Portal and systemic blood endotoxin concentrations were measured and the histomorphology of the intestinal mucosa was examined. Portal endotoxemia was observed 7 days after BDL and both portal and systemic endotoxemia were observed after 14 days. Portal endotoxemia was reversed by both internal and external biliary drainage and systemic endotoxemia was prevented. The ratio of villous height to crypt depth in the mucosa of the terminal ileum was decreased in rats with external drainage. Oral administration of endotoxin induced marked disruption of the mucosal epithelium in rats with external biliary drainage, but not in rats with internal biliary drainage. Significant increases in portal and systemic blood endotoxin concentrations were observed only in the external drainage group after oral endotoxin administration. The relief of biliary obstruction effectively relieved portal endotoxemia. External biliary drainage, however, has the potentially deleterious effect of disrupting the intestinal mucosa, which may promote the development of endotoxemia. These findings have implications for the use of biliary drainage procedures to reduce postoperative complications in jaundiced patients.