RESUMEN
Sudden death is usually the main finding in field animals during haemorrhagic septicaemia outbreaks caused by Pasteurella multocida type B:2 that causes acute, fatal and septicaemic disease in cattle and buffaloes. This situation may be due to failure in early detection of the disease where early treatment of antibiotics may improve the prognosis of the animal and other surviving animals. Thus, there is a grey area on the knowledge on the potential usage of pro-inflammatory cytokines and acute phase proteins as early biomarkers in the diagnosis of haemorrhagic septicaemia. In addition, exploration of the cerebrospinal fluid during infection has never been studied before. Therefore, this study was designed to fill up the grey areas in haemorrhagic septicaemia research. Twenty-one buffalo calves were divided into seven treatment groups where group 1 was inoculated orally with 10 mL of sterile phosphate-buffered saline pH 7 which act as a negative control group. Groups 2 and 3 were inoculated orally and subcutaneously with 10 mL of 1012 colony-forming unit of P. multocida type B:2. Group 4 and 5 buffaloes were inoculated orally and intravenously with 10 mL of lipopolysaccharide broth. Groups 6 and 7 were administered orally and subcutaneously with 10 mL of outer membrane protein broth. During the post-infection period of 21 days, blood and cerebrospinal fluid were sampled for the analyses of pro-inflammatory cytokines, acute phase proteins and cytological examination. Buffalo calves infected with P. multocida and its immunogens via different routes of inoculation showed significant changes (p < 0.05) of pro-inflammatory cytokines, acute phase proteins and cytological changes in both the serum and cerebrospinal fluid. Buffalo calves from groups 3 and 7 showed the highest pro-inflammatory cytokines, whereas group 6 had the highest acute phase protein concentration and group 5 revealed the highest value for cytology changes. In summary, results obtained in this study could be used as a profiling study to add novel knowledge to the haemorrhagic septicaemia research as well as the development of biomarkers.
Asunto(s)
Proteínas de Fase Aguda/metabolismo , Búfalos/sangre , Citocinas/sangre , Septicemia Hemorrágica/veterinaria , Infecciones por Pasteurella/veterinaria , Pasteurella multocida , Animales , Bovinos , Septicemia Hemorrágica/sangre , Lipopolisacáridos , Infecciones por Pasteurella/sangreRESUMEN
Shiga toxins (Stx) have a definite role in the development of hemolytic uremic syndrome in children with hemorrhagic colitis caused by pathogenic Stx-producing Escherichia coli (STEC) strains. The dramatic effects of these toxins on the microvasculature of different organs, particularly of the kidney, are well known, whereas there is no consensus on the mechanism by which Stx reach the endothelia of target organs and/or indirectly injure these body sites. We hereby describe a quick (4 h), radioactive, Raji cell-based method designed for the detection of Stx in human sera. The assay monitors the translation impairment induced by these powerful inhibitors of protein synthesis, which are identified properly by neutralizing their activity with specific monoclonal antibodies. By this method, we detected for the first time the functional activity of Stx in sera of STEC-infected patients during hemorrhagic colitis. Recent research has pointed to a dynamic process of Stx-induced renal intoxication in which concurrent and interactive steps are involved. Our rapid and specific method could be useful for studying the kinetics of Stx during the natural course of STEC infection and the interplay between Stx activity in serum and Stx presence in different blood fractions (neutrophils, monocytes, platelets, leukocyte-platelet aggregates, microvesicles, lipoproteins).
Asunto(s)
Síndrome Hemolítico-Urémico/tratamiento farmacológico , Toxinas Shiga/sangre , Toxinas Shiga/toxicidad , Anticuerpos Monoclonales/análisis , Anticuerpos Monoclonales/farmacología , Línea Celular , Niño , Infecciones por Escherichia coli/sangre , Infecciones por Escherichia coli/tratamiento farmacológico , Síndrome Hemolítico-Urémico/microbiología , Septicemia Hemorrágica/sangre , Humanos , Inhibidores de la Síntesis de la Proteína/sangre , Inhibidores de la Síntesis de la Proteína/farmacología , Inhibidores de la Síntesis de la Proteína/toxicidad , Toxinas Shiga/antagonistas & inhibidores , Escherichia coli Shiga-Toxigénica/patogenicidadRESUMEN
This report describes the proliferation and transmission patterns of Pasteurella multocida B:2 among stressful goats, created through dexamethasone injections. Thirty seven clinically healthy adult goats were divided into three groups consisted of 15 goats in group A, 11 goats in group B and the remaining 11 in group C. At the start of the study, all goats of group A were exposed intranasally to 1.97 x 10(10) CFU/ml of live P multocida B:2. Dexamethasone was immediately administered intramuscularly for 3 consecutive days at a dosage rate of 1 mg/kg. The exposed goats were observed for signs of HS for a period of 1 month. At the end of the 1-month period, 11 goats from group B were introduced into and commingled with the surviving goats of group A before all goats from both groups were immediately injected intramuscularly with dexamethasone for 3 consecutive days. The treatment with dexamethasone was then carried out at monthly interval throughout the 3-month study period. Goats of group C were kept separately as negative control. Three surviving goats from each group were killed at 2-week interval for a complete post-mortem examination. Two (13%) goats of group A were killed within 24 hours after intranasal exposure to P multocida B:2 while another two (13%) goats from the same group were killed on day 40, approximately 10 days after the second dexamethasone injection. All four goats showed signs and lesions typical of haemorrhagic septicaemia. Bacteraemia was detected in 3 goats of group A that were having rectal temperature higher than 41degrees C. The P. multocida B:2 isolation pattern was closely associated with dexamethasone injections when significantly (p < 0.05) higher rate of isolations from both groups were observed after each dexamethasone injection. Transmission of P multocida B:2 from goats of group A to group B was successful when P multocida B:2 was isolated from goats of group B for a period of 28 days. There was a strong correlation between dexamethasone injections, rate of bacterial isolation and serum cortisol level. The IgG level showed an increasing trend 2 weeks after exposure to P multocida B:2 and remained high throughout the study period.
Asunto(s)
Portador Sano/veterinaria , Enfermedades de las Cabras/microbiología , Enfermedades de las Cabras/transmisión , Septicemia Hemorrágica/veterinaria , Pasteurella multocida/crecimiento & desarrollo , Estrés Fisiológico/veterinaria , Animales , Anticuerpos Antibacterianos/sangre , Portador Sano/microbiología , Portador Sano/transmisión , Dexametasona/administración & dosificación , Ensayo de Inmunoadsorción Enzimática/veterinaria , Cabras , Septicemia Hemorrágica/sangre , Septicemia Hemorrágica/microbiología , Septicemia Hemorrágica/transmisión , Hidrocortisona/sangre , Mucosa Nasal/microbiología , Radioinmunoensayo/veterinaria , Estrés Fisiológico/sangre , Estrés Fisiológico/inducido químicamente , Estrés Fisiológico/microbiologíaRESUMEN
Contact with the Lonomia caterpillar causes numerous accidents, especially in Venezuela and the southern region of Brazil, where it is considered a public health problem. The Lonomia obliqua venom causes disseminated intravascular coagulation and a consumptive coagulopathy, which can lead to a hemorrhagic syndrome. The venom of Lonomia achelous also causes hemorrhage, but through increased fibrinolysis. In vivo and in vitro studies have shown that the venom of the Lonomia caterpillar contains several toxins with procoagulant, anticoagulant and antithrombotic activities. These toxins also affect the endothelium. The recent construction of cDNA libraries of the transcripts from L. obliqua bristles enables the use of biotechnological approaches to study the venom. This paper presents an overview of the biochemical and biological properties of Lonomia caterpillar venom, discussing aspects of human accidents, experimental envenomation, toxins and targets and future perspectives.
Asunto(s)
Venenos de Artrópodos/envenenamiento , Mordeduras y Picaduras/sangre , Septicemia Hemorrágica/sangre , Lepidópteros , Animales , Venenos de Artrópodos/química , Pruebas de Coagulación Sanguínea , Septicemia Hemorrágica/inducido químicamente , HumanosRESUMEN
Although the role of interleukin (IL)-6 in inflammatory diseases has been previously examined, its role in hemostasis, fibrinolysis, and coagulation during inflammation remains to be established. The present study elucidated the role of IL-6 in hemostatic and coagulatory changes during severe inflammation induced by intraperitoneal administration of lipopolysaccharide (LPS: 1 mg/kg) using IL-6 null (-/-) mice. After LPS challenge, IL-6 (-/-) mice revealed significant prolongation of prothrombin time and activated partial thromboplastin time and a significant decrease in platelet counts as compared with wild type mice. LPS treatment induced marked pulmonary hemorrhage with neutrophilic inflammation in IL-6 (-/-) mice, in contrast, only mild neutrophilic infiltration in WT mice confirmed by macroscopic and histological findings. The protein levels of proinflammatory mediators, such as IL-1 beta, macrophage inflammatory protein (MIP)-1 alpha, MIP-2, macrophage chemoattractant protein-1, granulocyte/macrophage-colony-stimulating factor, and keratinocyte chemoattractant in the lungs were significantly greater in IL-6 (-/-) mice than in WT mice after LPS challenge. These results directly indicate that IL-6 is protective against coagulatory and hemostatic disturbance and subsequent pulmonary hemorrhage induced by bacterial endotoxin, at least partly, via the modulation of proinflammatory processes.
Asunto(s)
Hemostasis , Interleucina-6/fisiología , Animales , Coagulación Sanguínea/efectos de los fármacos , Citocinas/sangre , Fibrinólisis/efectos de los fármacos , Genotipo , Septicemia Hemorrágica/sangre , Septicemia Hemorrágica/genética , Hemostasis/efectos de los fármacos , Inflamación , Interleucina-6/deficiencia , Interleucina-6/genética , Lipopolisacáridos/administración & dosificación , Enfermedades Pulmonares/sangre , Enfermedades Pulmonares/genética , Enfermedades Pulmonares/inmunología , Ratones , Ratones NoqueadosRESUMEN
The hemorrhagic syndrome caused by accidents with caterpillars of the genus Lonomia has been the focus of several clinical and biochemical studies, since its venom is composed of many active principles that interfere with the hemostatic system. Whereas a fibrinolytic agent has been characterized in the venom of Lonomia achelous, in Lonomia obliqua, only a prothrombin activator activity has been reported so far, even though both species cause similar bleeding disorders, characterized by hemorrhage, disseminated intravascular coagulation (DIC), and acute renal failure. Considering the possibility that the hemorrhagic syndrome resulting from envenoming by L. obliqua may be due to fibrinolytic and procoagulant activities acting together, we decided to investigate the effects of bristle extract (BE) of this species upon blood coagulation and fibrin(ogen)olysis. This study shows that besides a procoagulant activity related to the activation of prothrombin, the venom contains at least one fibrin(ogen)olytic activity, as shown by fibrinolysis in a fibrin (F) plate assay, by interference in thrombin-catalyzed fibrinocoagulation, and by polyacrylamide gel electrophoresis profile of fibrin and fibrinogen (Fg) degradation. Considering that a recombinant prothrombin activator from L. obliqua has been suggested in other studies to be used as an anti-thrombotic agent, it is important in the first place to better characterize the different active principles of this venom.
Asunto(s)
Factores de Coagulación Sanguínea , Pruebas de Coagulación Sanguínea , Fibrinólisis/fisiología , Septicemia Hemorrágica/sangre , Mariposas Nocturnas , Animales , Deficiencia del Factor X/sangre , Septicemia Hemorrágica/etiología , Humanos , Larva , Mariposas Nocturnas/crecimiento & desarrolloRESUMEN
Fifty-seven young buffaloes were experimentally infected or naturally exposed to haemorrhagic septicaemia (HS). Of these animals 32 became immune carriers. They were observed in groups for periods up to 360 days to monitor the appearance of pasteurellae in the nasopharynx and antibody status. In most animals pasteurellae appeared in the nasopharynx for a short period initially and disappeared. The organism reappeared intermittently and the longest observed period of reappearance was 215 days after exposure. All animals showed rising antibody titres with a peak lasting for 150 to 180 days and declining thereafter. Pasteurellae persisted in the tonsils and were isolated from 20 out of 27 carriers after slaughter. The longest period when isolation was made after slaughter was 229 days. The organism lodged in the tonsils was unaffected by antibacterial therapy using drugs to which the organism displayed in vitro sensitivity. It is concluded that in HS, carrier animals exist in an active as well as a latent state, the former appearing for short intermittent periods between long latent periods, when pasteurellae continue to remain in the tonsils which constitute a long-term reservoir.