RESUMO
BACKGROUND: The choroid plexus (CP), main component of blood-cerebrospinal fluid barrier (BCSFB), protects the brain from peripheral inflammation similar to the blood-brain barrier. Thus, CP is considered a critical target site of oxidative damage, which in sepsis oxidative stress is likely to be a major step in the development of brain damage. Functional alterations in CP may be associated with sepsis-induced brain injury. However, there is no description on the mechanisms associated with BCSFB disruption during sepsis development. MATERIALS AND METHODS: To test this hypothesis, we examined time-dependent oxidative stress markers in CP and permeability of BCSFB in rats submitted to polymicrobial sepsis by cecal ligation and puncture (CLP) or sham surgery (control). We assessed albumin cerebrospinal fluid/plasma concentration quotient (Qalb), an index of BCSFB dysfunction and in CP samples, the oxidative damage in lipids, proteins, antioxidant enzymes and nitrite/nitrate (N/N) concentration in 12, 24 and 48â¯h after CLP. RESULTS: The increase of BCSFB permeability is time-related to the increase of N/N concentration, oxidative damage to lipid and proteins, and decrease of antioxidant enzyme superoxide dismutase activity at 12â¯h in the CP; and decrease of catalase activity in 12 and 24â¯h. CONCLUSIONS: In experimental sepsis the BCSFB dysfunction occurs and oxidative stress seems to be a major step in this dysfunction.
Assuntos
Plexo Corióideo/irrigação sanguínea , Estresse Oxidativo , Sepse/sangue , Sepse/líquido cefalorraquidiano , Animais , Antioxidantes/metabolismo , Biomarcadores/sangue , Biomarcadores/líquido cefalorraquidiano , Permeabilidade Capilar , Ceco/microbiologia , Ceco/cirurgia , Modelos Animais de Doenças , Ligadura , Peroxidação de Lipídeos , Masculino , Carbonilação Proteica , Punções , Ratos Wistar , Sepse/microbiologia , Albumina Sérica/líquido cefalorraquidiano , Fatores de TempoRESUMO
The aim of this study was to analyze the effect of IL-1ra (an Interleukin-1 receptor antagonist) on sepsis-induced alterations in vasopressin (AVP) and nitric oxide (NO) levels. In addition, IL-1ra effect on the hypothalamic nitric oxide synthase (NOS) activities and survival rate was also analyzed. After Wistar rats were intracerebroventricular injected with IL-1ra (9 pmol) or vehicle (PBS 0.01 M), sepsis was induced by cecal-ligation and puncture (CLP). Blood, CSF, and hypothalamic samples were collected from different groups of rats (n = 8/group) after 4, 6, and 24 h. AVP and NO levels were greatly increased in CLP. Both total NOS and inducible NOS (iNOS) activities were also greatly increased in CLP rats. These changes in AVP, NO, and NOS were not observed in sham-operated control rats. IL-1ra administration did not alter plasma AVP levels after 4 and 6 h as compared to vehicle in CLP animals but after 24 h were significantly (P < 0.01) higher in IL-1ra-treated animals. IL-1ra administration significantly (P < 0.01) decreased NO concentration in CSF but not in plasma. Both total NOS and iNOS activities were also significantly decreased by IL-1ra at 24 h in CLP animals. Moreover, the 24 h survival rate of IL-1ra-treated rats increased by 38 % in comparison to vehicle administered animals. The central administration of IL-1ra increased AVP secretion in the late phase of sepsis which was beneficial for survival. We believe that one of the mechanisms for this effect of IL-1ra is through reduction of NO concentration in CSF and hence lower hypothalamic iNOS activities in the septic rats.
Assuntos
Arginina Vasopressina/sangue , Hipotálamo/metabolismo , Interleucina-1beta/sangue , Óxido Nítrico Sintase/metabolismo , Óxido Nítrico/líquido cefalorraquidiano , Receptores de Interleucina-1/antagonistas & inibidores , Sepse/metabolismo , Animais , Modelos Animais de Doenças , Óxido Nítrico/sangue , Óxido Nítrico Sintase Tipo II/metabolismo , Ratos , Ratos Wistar , Sepse/sangue , Sepse/líquido cefalorraquidianoRESUMO
We studied 310 strains of Staphylococcus spp. from neonates admitted in intensive care unit from june 1988 to may 1990, with the purpose of establishing a relationship between the slime production and the occurrence of sepsis. The original technique for its determination was modified; this facilitated the performance and the reading of results. Of 105 neonates with isolation in blood, spinal fluid and/or intravascular catheter of negative-coagulase Staphylococcus (CNS), the incidence of sepsis was 57.9% when the strain was a slime-producer, and only 11.6% when the strain did not produce slime (p less than 0.001). The risk of infection was five-fold increased when the isolated was slime-producer CNS. We proved a high predictive value when the strains were identical and isolated from two samples, one of which was blood. These results show that the production of slime is a factor which strongly support the diagnosis of neonatal sepsis due to negative-coagulase Staphylococcus.
Assuntos
Proteínas de Bactérias/biossíntese , Polissacarídeos Bacterianos/biossíntese , Sepse/diagnóstico , Infecções Estafilocócicas/diagnóstico , Staphylococcus/metabolismo , Biomarcadores , Sangue/microbiologia , Cateteres de Demora , Líquido Cefalorraquidiano/microbiologia , Coagulase/análise , Contaminação de Equipamentos , Humanos , Incidência , Recém-Nascido , Valor Preditivo dos Testes , Estudos Prospectivos , Risco , Sepse/sangue , Sepse/líquido cefalorraquidiano , Sepse/epidemiologia , Sepse/microbiologia , Infecções Estafilocócicas/microbiologia , Staphylococcus/enzimologia , Staphylococcus/isolamento & purificação , Staphylococcus/patogenicidade , VirulênciaRESUMO
De los pacientes sépticos quirúrgicos ingresados en el Hospital de Enfermedades Infecciosas "Francisco J. Muñiz" de Buenos Aires, República Argentina, desde el 1§ de junio de 1979 hasta el 30 de junio de 1985, se estudia una serie de 266 casos, que incluye flemones urinosos, gangrenas gaseosas, celulitis y otras afecciones infecciosas. Dichos enfermos fueron anestesiados mediante bloqueo intradural con agentes anestésicos hiperbáricos; en 54 de ellos se efectuó el análisis químico y bacteriológico del L.C.R. con muestras obtenidas: a) previa a la anestesia; b) 30 segundos después de inyectada la sustancia anestésica y c) control a las 24 hs. El análisis seriado del L.C.R. y el seguimiento clínico de los enfermos permite establecer que no existen modificaciones significativas al comparar con un grupo control de 7 pacientes no infectados. Por lo tanto de esta experiencia puede inferirse que la anestesia mediante el bloqueo raquídeo puede realizarse en estos pacientes sin aparición posterior de signosintomatología meníngea infecciosa
Assuntos
Humanos , Masculino , Feminino , Raquianestesia , Sepse/líquido cefalorraquidianoRESUMO
De los pacientes sépticos quirúrgicos ingresados en el Hospital de Enfermedades Infecciosas "Francisco J. Muñiz" de Buenos Aires, República Argentina, desde el 1º de junio de 1979 hasta el 30 de junio de 1985, se estudia una serie de 266 casos, que incluye flemones urinosos, gangrenas gaseosas, celulitis y otras afecciones infecciosas. Dichos enfermos fueron anestesiados mediante bloqueo intradural con agentes anestésicos hiperbáricos; en 54 de ellos se efectuó el análisis químico y bacteriológico del L.C.R. con muestras obtenidas: a) previa a la anestesia; b) 30 segundos después de inyectada la sustancia anestésica y c) control a las 24 hs. El análisis seriado del L.C.R. y el seguimiento clínico de los enfermos permite establecer que no existen modificaciones significativas al comparar con un grupo control de 7 pacientes no infectados. Por lo tanto de esta experiencia puede inferirse que la anestesia mediante el bloqueo raquídeo puede realizarse en estos pacientes sin aparición posterior de signosintomatología meníngea infecciosa (AU)