Degree of endothelium injury promotes fibroelastogenesis in experimental acute lung injury

We tested the hypothesis that at the early phase of acute lung injury (ALI) the degree of endothelium injury may predict lung parenchyma remodelling For this purpose, two models of extrapulmonary ALI induced by Escherichia col: lipopolysaccharide (ALI-LPS) or cecal ligation and puncture (ALI-CLP) were developed in mice At day 1, these models had similar degrees of lung mechanical compromise, epithelial damage, and intraperitoneal inflammation, but endothelial lesion was greater in ALI-CLP A time course analysis revealed, at day 7 ALI-CLP had higher degrees of epithelial lesion, denudation of basement membrane, endothelial damage, elastic and collagen fibre content, neutrophils in bronchoalveolar lavage fluid (BALF), peritoneal fluid and blood, levels of interleukin-6, KC (murine analogue of IL-8), and transforming growth factor-beta in BALF Conversely, the number of lung apoptotic cells was similar in both groups In conclusion, the intensity of fibroelastogenesis was affected by endothelium injury in addition to the maintenance of epithelial damage and intraperitoneal inflammation. (C) 2010 Elsevier B V All rights reserved

Hypervolemia induces and potentiates lung damage after recruitment maneuver in a model of sepsis-induced acute lung injury

Introduction: Recruitment maneuvers (RMs) seem to be more effective in extrapulmonary acute lung injury (ALI), caused mainly by sepsis, than in pulmonary ALI. Nevertheless, the maintenance of adequate volemic status is particularly challenging in sepsis. Since the interaction between volemic status and RMs is not well established, we investigated the effects of RMs on lung and distal organs in the presence of hypovolemia, normovolemia, and hypervolemia in a model of extrapulmonary lung injury induced by sepsis. Methods: ALI was induced by cecal ligation and puncture surgery in 66 Wistar rats. After 48 h, animals were anesthetized, mechanically ventilated and randomly assigned to 3 volemic status (n = 22/group): 1) hypovolemia induced by blood drainage at mean arterial pressure (MAP)approximate to 70 mmHg; 2) normovolemia (MAP approximate to 100 mmHg), and 3) hypervolemia with colloid administration to achieve a MAP approximate to 130 mmHg. In each group, animals were further randomized to be recruited (CPAP = 40 cm H(2)O for 40 s) or not (NR) (n = 11/group), followed by 1 h of protective mechanical ventilation. Echocardiography, arterial blood gases, static lung elastance (Est, L), histology (light and electron microscopy), lung wet-to-dry (W/D) ratio, interleukin (IL)-6, IL-1 beta, caspase-3, type III procollagen (PCIII), intercellular adhesion molecule-1 (ICAM-1), and vascular cell adhesion molecule-1 (VCAM-1) mRNA expressions in lung tissue, as well as lung and distal organ epithelial cell apoptosis were analyzed. Results: We observed that: 1) hypervolemia increased lung W/D ratio with impairment of oxygenation and Est, L, and was associated with alveolar and endothelial cell damage and increased IL-6, VCAM-1, and ICAM-1 mRNA expressions; and 2) RM reduced alveolar collapse independent of volemic status. In hypervolemic animals, RM improved oxygenation above the levels observed with the use of positive-end expiratory pressure (PEEP), but increased lung injury and led to higher inflammatory and fibrogenetic responses. Conclusions: Volemic status should be taken into account during RMs, since in this sepsis-induced ALI model hypervolemia promoted and potentiated lung injury compared to hypo-and normovolemia.

Description of Nosocomial Infection Prevention Practices by Anesthesiologists in a University Hospital

Kishi D; Videira RLR Description of Nosocomial Infection Prevention Practices by Anesthesiologists in a University Hospital. Background and objectives: Anesthesiologists play an important role in the prevention of nosocomial infections. In anesthetic practice, physiologic barriers are routinely breached, allowing patient contamination with microorganisms and the consequent development of infection. The lack of adhesion to recommended practices can facilitate transmission of microorganisms. It is important to describe prophylactic practices of anesthesia-related nosocomial infections performed by anesthesiologists. Methods: Structured questionnaires were distributed to be answered voluntarily and anonymously by anesthesiologists. Results: Among 112 anesthesiologists, 75% answered the questionnaire. Surgical mask is used by 95.2% of anesthesiologists, 96.3% wear gloves frequently, 98.9% wear sterile gloves for neuraxial block, 91.3% use sterile technique for central venous puncture, 95.1% wash their hands between cases, 91.6% try to maintain the endotracheal tube sterile, 96.3% discard the prefilled propofol syringe at the end of each anesthesia, 30% clean the vials before using it in the neuraxial blocks, and 19.8% clean the vials before intravenous use. Conclusions: Respondents showed good adhesion to practices of nosocomial infection prophylaxis and to improve them educational multidisciplinary campaigns are necessary.

Endoscopic-guided percutaneous radiofrequency cordotomy

The authors present the first clinical implementation of an endoscopic-assisted percutaneous anterolateral radiofrequency cordotomy. The aim of this article is to demonstrate the intradural endoscopic visualization of the cervical spinal cord via a percutaneous approach to refine the spinal target for anterolateral cordotomy, avoiding undesired trauma to the spinal tissue or injury to blood vessels. Initially, a lateral puncture of the spinal canal in the C1-2 interspace is performed, guided by fluoroscopy. As soon as CSF is reached by the guide cannula (17-gauge needle), the endoscope can be inserted for visualization of the spinal cord and its surrounding structures. The endoscopic visualization provided clear identification of the pial surface of the spinal cord, arachnoid membrane, dentate ligament, dorsal and ventral root entry zone, and blood vessels. The target for electrode insertion into the spinal cord was determined to be the midpoint from the dentate ligament and the ventral root entry zone. The endoscopic guidance shortened the fluoroscopy usage time and no intrathecal contrast administration was needed. Cordotomy was performed by a standard radiofrequency method after refining of the neurophysiological target. Satisfactory analgesia was provided by the procedure with no additional complications or CSF leak. The initial use of this technique suggests that a percutaneous endoscopic procedure may be useful for particular manipulation of the spinal cord, possibly adding a degree of safety to the procedure and improving its effectiveness. (DOI: 10.3171/2010.4.JNS091779)

EFFECTS OF A POTENT PEROXYNITRITE DECOMPOSITION CATALYST IN MURINE MODELS OF ENDOTOXEMIA AND SEPSIS

Excessive free-radical production due to various bacterial components released during bacterial infection has been linked to cell death and tissue injury. Peroxynitrite is a highly reactive oxidant produced by the combination of nitric oxide (NO) and superoxide anion, which has been implicated in cell death and tissue injury in various forms of critical illness. Pharmacological decomposition of peroxynitrite may represent a potential therapeutic approach in diseases associated with the overproduction of NO and superoxide. In the present study, we tested the effect of a potent peroxynitrite decomposition catalyst in murine models of endotoxemia and sepsis. Mice were injected i.p. with LPS 40 mg/kg with or without FP15 [Fe(III) tetrakis-2-(N-triethylene glycol monomethyl ether) pyridyl porphyrin] (0.1, 0.3, 1, 3, or 10 mg/kg per hour). Mice were killed 12 h later, followed by the harvesting of samples from the lung, liver, and gut for malondialdehyde and myeloperoxidase measurements. In other subsets of animals, blood samples were obtained by cardiac puncture at 1.5, 4, and 8 h after LPS administration for cytokine (TNF-alpha, IL-1 beta, and IL-10), nitrite/nitrate, alanine aminotransferase, and blood urea nitrogen measurements. Endotoxemic animals showed an increase in survival from 25% to 80% at the FP15 doses of 0.3 and 1 mg/kg per hour. The same dose of FP15 had no effect on plasma levels of nitrite/nitrate. There was a reduction in liver and lung malondialdehyde in the endotoxemic animals pretreated with FP15, as well as in hepatic myeloperoxidase and biochemical markers of liver and kidney damage (alanine aminotransferase and blood urea nitrogen). In a bacterial model of sepsis induced by cecal ligation and puncture, FP15 treatment (0.3 mg/kg per day) significantly protected against mortality. The current data support the view that peroxynitrite is a critical factor mediating liver, gut, and lung injury in endotoxemia and septic shock: its pharmacological neutralization may be of therapeutic benefit.

Percutaneous ultrasound-guided renal biopsy in children - safety, efficacy, indications and renal pathology findings: 14-year Brazilian university hospital

Introduction: Pediatric percutaneous renal biopsy (Bx) is a routine procedure in pediatric nephrology to obtain renal tissues for histological study. We evaluated the safety, efficacy, indications and renal findings of this procedure at a tertiary care pediatric university hospital and compared our findings with the literature. Methods: Retrospective study based on medical records from January 1993 to June 2006. Results: In the study period, 305 Bx were performed in 262 patients, 127 (48.5%) male, aged 9.8 +/- 4.2 years. A 16-gauge needle was utilized in 56/305 Bx, an 18-gauge needle in 252/305 Bx (82.6%). 56.1% Bx were performed under sedation plus local anesthesia, 43.9% under general anesthesia. The number of punctures per Bx was 3.1 +/- 1.3. Minor complications occurred in 8.6% procedures. The 16-gauge needle caused a higher frequency of renal hematomas (p = 0.05). The number of glomeruli per puncture was >= 5 in 96.7% and >= 7 in 92%. Glomeruli number per puncture and frequency of complications were not different according to the type of anesthesia used. A renal pathology diagnosis was achieved in 93.1% Bx. The main indications of Bx were nephrotic syndrome (NS), lupus nephritis (LN) and hematuria (HE). The diagnosis of minimal change disease (MCD) (61.3%), class V (35.6%) and IgA nephropathy (26.3%) predominated in NS, LN and HE patients, respectively. Conclusion: Pediatric real-time ultrasound-guided percutaneous renal biopsy was safe and effective. The main clinical indications for Bx were NS and LN, the predominant renal pathology diagnoses were MCD and class V LN.

Neurosyphilis in HIV-infected patients: Clinical manifestations, serum venereal disease research laboratory titers, and associated factors to symptomatic neurosyphilis

Goal: To describe clinical and laboratory features of human immunodeficiency infection (HIV)-infected patients with neurosyphilis. Study Design: Retrospective study of 27 consecutive cases of HIV-infected patients with a positive Venereal Disease Research Laboratory (VDRL) in cerebrospinal fluid (CSF). Results: Median of age was 36 years and 89% were men. Ten (37%) patients had previous nonneurologic syphilis treatment. At the time of neurosyphilis diagnosis, 10 (37%) patients had early syphilis, and 6 of them were neurologically asymptomatic. Nine (33%) patients had symptomatic neurosyphilis. Twenty-six (96%) patients were classified with early neurosyphilis. The medians of serum VDRL and CD4(+) T cell counts were 1:128 and 182 cell/mu L, respectively. Twenty five (93%) patients presented serum VDRL titers >= 1:16. Five of 6 patients with early syphilis and asymptomatic neurosyphilis, presented serum VDRL >= 1:16. Symptomatic patients showed lower CD4(+) T cell counts (59 cell/mu L vs. 208 cell/mu L, P = 0.03) and higher protein concentration on CSF (118 mg/dL vs. 39 mg/dL, P <0.001) than asymptomatic patients. Conclusions: Most patients had early and asymptomatic neurosyphilis, and more than one third had early syphilis. Patients with symptomatic neurosyphilis showed lower CD4(+) T cell counts and higher protein concentration on CSF than those asymptomatic. Most patients had serum VDRL titers >= 1:16, regardless of syphilis stage.

Spinal Myoclonus after Subarachnoid Anesthesia with Bupivacaine

Abrao J, Bianco MP, Roma W, Krippa JAS, Hallak JE - Spinal Myoclonus after Subarachnoid Anesthesia with Bupivacaine. Background and objectives: It is presented in this case report a very rare complication after spinal anesthesia to provide subsidies to the management and therapeutic conduct. Case report: This is a 63-year old African-Brazilian patient, ASA I, scheduled for transurethral resection of the prostate (TURP). He underwent subarachnoid anesthesia with bupivacaine (15 mg) without adrenaline. Intercurrences were not observed during puncture, and the patient was positioned for surgery. Soon after positioning the patient, he complained of severe pain in the perineum region followed by involuntary tonic-clonic movements of the lower limbs. The patient was treated with a benzodiazepine to control the myoclonus without response. This episode was followed by significant agitation and the patient was intubated. He was maintained in controlled ventilation and transferred to the Intensive Care Unit. Despite all biochemical and imaging tests performed, an apparent cause was not detected. The medication was not changed and the same batch of anesthetic had been used in other patients that same day without intercurrences. Conclusions: After ruling out all possible causes, the diagnosis of spinal myoclonus after spinal anesthesia with bupivacaine was made by exclusion.

IL-17 Receptor Signaling Is Required to Control Polymicrobial Sepsis

Sepsis is a systemic inflammatory response resulting from the inability of the host to contain the infection locally. Previously, we demonstrated that during severe sepsis there is a marked failure of neutrophil migration to the infection site, which contributes to dissemination of infection, resulting in high mortality. IL-17 plays an important role in neutrophil recruitment. Herein, we investigated the role of IL-17R signaling in polymicrobial sepsis induced by cecal ligation and puncture (CLP). It was observed that IL-17R-deficient mice, subjected to CLP-induced non-severe sepsis, show reduced neutrophil recruitment into the peritoneal cavity, spread of infection, and increased systemic inflammatory response as compared with C57BL/6 littermates. As a consequence, the mice showed an increased mortality rate. The ability of IL-17 to induce neutrophil migration was demonstrated in vivo and in vitro. Beside its role in neutrophil recruitment to the infection focus, IL-17 enhanced the microbicidal activity of the migrating neutrophils by a mechanism dependent on NO. Therefore, IL-17 plays a critical role in host protection during polymicrobial sepsis. The Journal of Immunology, 2009, 182: 7846-7854.

DIVERGENT ROLE OF HEME OXYGENASE INHIBITION IN THE PATHOGENESIS OF SEPSIS

The reduction of neutrophil migration to an infectious focus is associated with a high mortality in severe sepsis. Previously, we showed that heme oxygenase (HO) products downregulate neutrophil recruitment in a noninfectious inflammatory model. The present study was designed to determine the role of HO in sepsis induced by cecal ligation and puncture (CLP) model. We demonstrated that pretreatment, but not the combination of pretreatment plus posttreatment with zinc protoporphyrin IX (ZnPP IX), an HO inhibitor, prevented the reduction of CXCR2 on circulating neutrophils and the failure of intraperitoneal neutrophil migration to the site of infection. Consequently, bacterial dissemination, systemic inflammatory response, and organ injury were prevented. In addition, pretreatment with the HO inhibitor avoided hypotension and consequently increased survival. Moreover, in mice subjected to severe CLP, the pretreatment, but not the combination of pretreatment plus posttreatment with ZnPP IX, prevented the increase of plasmatic free heme observed in nontreated severe CLP. The administration of exogenous hemin to mice subjected to moderate sepsis consistently increased the mortality rate. Furthermore, hemin resulted in a reduction of neutrophil migration both in vivo and in vitro. Altogether, our results demonstrated that pretreatment with the HO inhibitor prevents the pathological findings in severe CLP. However, the combination of pretreatment plus posttreatment with ZnPP IX enhances sepsis severity because of an increase in circulating levels of heme, which is deleterious to the host tissues and also inhibits neutrophil migration.

Hydrogen sulfide augments neutrophil migration through enhancement of adhesion molecule expression and prevention of CXCR2 internalization: Role of ATP-sensitive potassium channels

In this study, we have addressed the role of H2S in modulating neutrophil migration in either innate (LPS-challenged naive mice) or adaptive (methylated BSA (mBSA)-challenged immunized mice) immune responses. Treatment of mice with H S synthesis inhibitors, DL-propargylglycine (PAG) or beta-cyanoalanine, reduced neutrophil migration induced by LPS or methylated BSA (mBSA) into the peritoneal cavity and by mBSA into the femur/tibial joint of immunized mice. This effect was associated with decreased leukocyte rolling, adhesion, and P-selectin and ICAM-1 expression on endothelium. Predictably, treatment of animals with the H2S donors, NaHS or Lawesson`s reagent, enhanced these parameters. Moreover, the NaHS enhancement of neutrophil migration was not observed in ICAM-1-deficient mice. Neither PAG nor NaHS treatment changed LPS-induced CD18 expression on neutrophils, nor did the LPS- and mBSA-induced release of neutrophil chemoattractant mediators TNF-alpha, keratinocyte-derived chemokine, and LTB4. Furthermore, in vitro MIP-2-induced neutrophil chemotaxis was inhibited by PAG and enhanced by NaHS treatments. Accordingly, MIP-2-induced CXCR2 internalization was enhanced by PAG and inhibited by NaHS treatments. Moreover, NaHS prevented MIP-2-induced CXCR2 desensitization. The PAG and NaHS effects correlated, respectively, with the enhancement and inhibition of MIP-2-induced G protein-coupled receptor kinase 2 expression. The effects of NaHS on neutrophil migration both in vivo and in vitro, together with CXCR2 internalization and G protein-coupled receptor kinase 2 expression were prevented by the ATP-sensitive potassium (K-ATP(+)) channel blocker, glybenclamide. Conversely, diazoxide, a K-ATP(+) channel opener, increased neutrophil migration in vivo. Together, our data suggest that during the inflammatory response, H`S augments neutrophil adhesion and locomotion, by a mechanism dependent on K-ATP(+) channels.

Dual role of hydrogen sulfide in mechanical inflammatory hypernociception

Hydrogen Sulfide (H2S) is an endogenous gas involved in several biological functions, including modulation of nociception. However, the mechanisms involved in such modulation are not fully elucidated. The present Study demonstrated that the pretreatment of mice with PAG, a H2S synthesis inhibitor, reduced LPS-induced mechanical paw hypernociception. This inhibition of hypernociception was associated with the prevention of neutrophil recruitment to the plantar tissue. Conversely, PAG had no effect on LPS-induced production of the hypernociceptive cytokines, TNF-alpha, IL-1 beta and CXCL1/KC and on hypernociception induced by PGE(2), a directly acting hypernociceptive mediator. In contrast with the pro-nociceptive role of endogenous H2S. systemic administration of NaHS, a H2S donor, reduced LPS-induced mechanical hypernociception in mice. Moreover, this treatment inhibited mechanical hypernociception induced by PGE(2), suggesting a direct effect of H2S on nociceptive neurons. The antinociceptive mechanism of exogenous H2S depends on K-(ATP)(+) channels since the inhibition of PGE(2) hypernociception by NaHS was prevented by glibenclamide (K-(ATP)(+) channel blocker). Finally, NaHS did not alter the thermal nociceptive threshold in the hot-plate test, confirming that its effect is mainly peripheral. Taken together, these results suggest that H2S has a dual role in inflammatory hypernociception: 1. an endogenous pro-nociceptive effect due to up-regulation of neutrophil migration. and 2. an antinociceptive effect by direct blockade of nociceptor sensitization modulating K-(ATP)(+) channels. (c) 2008 Elsevier B.V. All rights reserved.

Inhibition of Neutrophil Migration by Hemopexin Leads to Increased Mortality Due to Sepsis in Mice

Rationale: The reduction of neutrophil migration to the bacterial focus is associated with poor outcome in sepsis. Objectives: The objective of this study was to identify soluble substances in the blood of septic mice that inhibit neutrophil migration. Methods: A pool of serum obtained from mice 2 hours after the induction of severe sepsis by cecal ligation and puncture inhibited the neutrophil migration. The proteins with inhibitory activity on neutrophil migration were isolated by Blue-Sepharose chromatography, high-performance liquid chromatography, and electrophoresis, and identified by mass spectrometry. Measurements and Main Results: Hemopexin was identified as the serum component responsible for the inhibition of neutrophil migration. In sepsis, the pretreatment of wild-type mice with hemopexin inhibited neutrophil migration to the focus of infection and decreased the survival rate from 87.5 to 50.0%. Hemopexin-null mice subjected to severe sepsis presented normal neutrophil migration, low bacteremia, and an improvement of 40% in survival rate. Moreover, hemopexin inhibited the neutrophil chemotaxis response evoked by C5a or macrophage inflammatory protein-2 and induced a reduction of CXCR2 and L-selectin as well as the up-regulation of CD11b expression in neutrophil membranes. The inhibitory effect of hemopexin on neutrophil chemotaxis was prevented by serine protease inhibitors or ATP. In addition, serum levels of ATP were decreased 2 hours after severe sepsis. Conclusions: These data demonstrate for the first time the inhibitory role of hemopexin in neutrophil migration during sepsis and suggest that the therapeutic inhibition of hemopexin or its protease activity could improve neutrophil migration to the focus of infection and survival in sepsis.

Essential Role of CCR2 in Neutrophil Tissue Infiltration and Multiple Organ Dysfunction in Sepsis

Rationale Sepsis is defined as a systemic inflammatory response to infection, which in its severe form is associated with multiple organ dysfunction syndrome (MODS). The precise mechanisms by Which MODS develops remain unclear. Neutrophils have a pivotal role in the defense against infections; however, overwhelming activation of neutrophils is known to elicit tissue damage. Objectives: We investigated the role of the chemokine receptor CCR2 in driving neutrophil infiltration and eliciting tissue damage in remote organs during sepsis. Methods: Sepsis was induced in wild-type mice treated with CCR2 antagonist (RS504393) or CCR2(-/-) mice by cecal ligation and puncture (CLP) model. Neutrophil infiltration into the organs was measured by myeloperoxidase activity and fluorescence-activated cell sorter. CCR2 expression and chemotaxis were determined in neutrophils stimulated with Toll-like receptor agonists or isolated from septic mice and patients. Measurements and Main Results: CCR2 expression and responsiveness to its ligands was induced in circulating neutrophils during CLP-induced sepsis by a mechanism dependent on Toll-like receptor/nuclear factor-kappa B pathway. Genetic or pharmacologic inhibition of CCR2 protected mice from CLP-induced mortality. This protection was associated with lower infiltration of neutrophils into the lungs, heart, and kidneys and reduced serum biochemical indicators of organ injury and dysfunction. Importantly, neutrophils from septic patients express high levels of CCR2, and the severity of patient illness correlated positively with increasing neutrophil chemotaxis to CCR2 ligands. Conclusions: Collectively, these data identify CCR2 as a key receptor that drives the inappropriate infiltration of neutrophils into remote organs during sepsis. Therefore, CCR2 blockade is a novel potential therapeutic target for treatment of sepsis-induced MODS.