Mammalian Toll-like receptors (TLRs) are expressed on innate immune cells and respond to the membrane components of Gram-positive or Gram-negative bacteria. When activated, they convey signals to transcription factors that orchestrate the inflammatory response. However, the intracellular signaling events following TLR activation are largely unknown. Here we show that TLR2 stimulation by Staphylococcus aureus induces a fast and transient activation of the Rho GTPases Rac1 and Cdc42 in the human monocytic cell line THP-1 and in 293 cells expressing TLR2. Dominant-negative Rac1N17, but not dominant-negative Cdc42N17, block nuclear factor-kappa B (NF-kappa B) transactivation. S. aureus stimulation causes the recruitment of active Rac1 and phosphatidylinositol-3 kinase (PI3K) to the TLR2 cytosolic domain. Tyrosine phosphorylation of TLR2 is required for assembly of a multiprotein complex that is necessary for subsequent NF-kappa B transcriptional activity. A signaling cascade composed of Rac1, PI3K and Akt targets nuclear p65 transactivation independently of I kappa B alpha degradation. Thus Rac1 controls a second, I kappa B-independent, pathway to NF-kappa B activation and is essential in innate immune cell signaling via TLR2.

Mutations in the TLR4 receptor may predispose people to develop septic shock with gram-negative microorganisms.

The toll-like receptor 2 (TLR2) has gained importance as a major mammalian receptor for lipoproteins derived from the cell wall of a variety of bacteria, such as Borrelia burgdorferi, Treponema pallidum, and Mycoplasma fermentans. We were interested in identifying mutations in the TLR2 gene that might prove to be associated with altered susceptibility to septic shock. We performed a mutation screen of the TLR2 gene using single-stranded conformational polymorphism in 110 normal, healthy study subjects and detected an Arg753Gln mutation in three individuals. No other missense mutations were detected in the TLR2 open reading frame. Functional studies demonstrate that the Arg753Gln polymorphism, in comparison to the wild-type TLR2 gene, is significantly less responsive to bacterial peptides derived from B. burgdorferi and T. pallidum. In a septic shock population, the Arg753Gln TLR2 polymorphism occurred in 2 out of 91 septic patients. More importantly, both of the subjects with the TLR2 Arg753Gln polymorphism had staphylococcal infections. These findings suggest that a mutation in the TLR2 gene may predispose individuals to lifethreatening bacterial infections.Microbial pathogens are a major health concern worldwide. Invasion of the host by microbial pathogens causes the activation of the innate immune response, which acts as a first line of defense against pathogenic bacteria. The innate immune response triggers a sequence of events that results in the production and secretion of cytokines and chemokines, activation of macrophages and monocytes, and in some cases initiation of adaptive immunity (10).The toll receptors appear to be very important in initiating the innate immune response. C3H/HeJ mice which have a mutation in the toll-like receptor 4 (TLR4) gene (Pro712His) and C57BL6/10ScCr mice which have a deletion of TLR4 are both hyporesponsive to lipopolysaccharide (LPS) (12). The TLR4 mutation in C3H/HeJ mice was the first direct proof for identifying TLR4 as a major LPS receptor in mammals. Subsequently TLR4 Ϫ/Ϫ mice were shown to be LPS hyporesponsive as well (6). Binding of LPS to TLR4, via a complex involving CD14 as well as MD-2, is thought to initiate a signaling cascade that involves several kinases and accessory molecules such as MyD88 and IRAK, leading eventually to a nuclear translocation of transcription factors NF-B and AP-1 (14). The binding of these transcription factors is responsible for initiating cytokine and chemokine expression subsequent to LPS exposure. Recently, mutations in the TLR4 receptor at residues 299 and 399 were shown to be associated with hyporesponsiveness to inhaled endotoxin in humans (2). Furthermore, the Asp299Gly TLR4 mutation may increase the risk to carriers of developing gram-negative septic shock (E. Lorenz, J. Mira, K. Frees, and D. Schwartz, submitted for publication). However, TLR4 does not seem to be involved in mediating the cellular response to gram-positive pathogens. TLR2, which is highly homologous to TLR4, has been shown to mediate a response to LPS, albei...

Intensive Care and Sepsis (CRICS) Group IMPORTANCE In the intensive care unit (ICU), orotracheal intubation can be associated with increased risk of complications because the patient may be acutely unstable, requiring prompt intervention, often by a practitioner with nonexpert skills. Video laryngoscopy may decrease this risk by improving glottis visualization. OBJECTIVE To determine whether video laryngoscopy increases the frequency of successful first-pass orotracheal intubation compared with direct laryngoscopy in ICU patients.DESIGN, SETTING, AND PARTICIPANTS Randomized clinical trial of 371 adults requiring intubation while being treated at 7 ICUs in France between May 2015 and January 2016; there was 28 days of follow-up.INTERVENTIONS Intubation using a video laryngoscope (n = 186) or direct laryngoscopy (n = 185). All patients received general anesthesia. MAIN OUTCOMES AND MEASURESThe primary outcome was the proportion of patients with successful first-pass intubation. The secondary outcomes included time to successful intubation and mild to moderate and severe life-threatening complications. RESULTS Among 371 randomized patients (mean [SD] age, 62.8 [15.8] years; 136 [36.7%] women), 371 completed the trial. The proportion of patients with successful first-pass intubation did not differ significantly between the video laryngoscopy and direct laryngoscopy groups (67.7% vs 70.3%; absolute difference, −2.5% [95% CI, −11.9% to 6.9%]; P = .60). The proportion of first-attempt intubations performed by nonexperts (primarily residents, n = 290) did not differ between the groups (84.4% with video laryngoscopy vs 83.2% with direct laryngoscopy; absolute difference 1.2% [95% CI, −6.3% to 8.6%]; P = .76). The median time to successful intubation was 3 minutes (range, 2 to 4 minutes) for both video laryngoscopy and direct laryngoscopy (absolute difference, 0 [95% CI, 0 to 0]; P = .95). Video laryngoscopy was not associated with life-threatening complications (24/180 [13.3%] vs 17/179 [9.5%] for direct laryngoscopy; absolute difference, 3.8% [95% CI, −2.7% to 10.4%]; P = .25). In post hoc analysis, video laryngoscopy was associated with severe life-threatening complications (17/179 [9.5%] vs 5/179 [2.8%] for direct laryngoscopy; absolute difference, 6.7% [95% CI, 1.8% to 11.6%]; P = .01) but not with mild to moderate life-threatening complications (10/181 [5.4%] vs 14/181 [7.7%]; absolute difference, −2.3% [95% CI, −7.4% to 2.8%]; P = .37).CONCLUSIONS AND RELEVANCE Among patients in the ICU requiring intubation, video laryngoscopy compared with direct laryngoscopy did not improve first-pass orotracheal intubation rates and was associated with higher rates of severe life-threatening complications. Further studies are needed to assess the comparative effectiveness of these 2 strategies in different clinical settings and among operators with diverse skill levels.

Information on the species causing Candida peritonitis, their in vitro susceptibility, antifungal strategies in this setting and patient outcome is still scarce. AmarCand was a prospective, non-interventional study in 271 adult intensive-care unit (ICU) patients with proven invasive Candida infection who received systemic antifungal therapy (France, 2005-2006). Of these ICU patients, 93 (median age 65 years, simplified acute physiology score II 52) had Candida peritonitis, including 73 nosocomial peritonitis, 53 concomitant bacterial peritoneal infections and 26 candidaemias. Candida species were C. albicans (n = 63/108 isolates, 58%), C. glabrata (n = 22, 20%), C. krusei (n = 9), C. kefyr (n = 5), C. parapsilosis (n = 3), C. tropicalis (n = 3), C. ciferii (n = 2) and C. lusitaniae (n = 1). Of tested isolates, 28% were fluconazole-resistant or susceptible dose-dependent (C. albicans 3/32, C. glabrata 9/14, C. krusei 4/4). Empiric antifungal treatment was started 1 day (median) after peritonitis diagnosis, with fluconazole (n = 2 patients), caspofungin (n = 12), voriconazole (n = 3), amphotericin B (n = 2), or a combination (n = 4). Following susceptibility testing, empiric antifungal treatment was judged inadequate in 9/45 (20%) patients and modified in 30 patients (fluconazole was replaced by caspofungin (n = 14) or voriconazole (n = 4)). Mortality in ICU was 38% (35/93) and was not influenced by type of Candida species, fluconazole susceptibility, time to treatment, candidaemia, nosocomial acquisition, or concomitant bacterial infection. No specific factors for death were identified. In summary, a high proportion of fluconazole-resistant or susceptible dose-dependent strains was cultured. These results confirm the high mortality rates of Candida peritonitis and plead for additional investigation in this population. Antifungal treatment for severe cases of Candida peritonitis in ICU patients remains the standard care.

The toll-like receptor 2 (TLR2) has gained importance as a major mammalian receptor for lipoproteins derived from the cell wall of a variety of bacteria, such as Borrelia burgdorferi, Treponema pallidum, and Mycoplasma fermentans. We were interested in identifying mutations in the TLR2 gene that might prove to be associated with altered susceptibility to septic shock. We performed a mutation screen of the TLR2 gene using single-stranded conformational polymorphism in 110 normal, healthy study subjects and detected an Arg753Gln mutation in three individuals. No other missense mutations were detected in the TLR2 open reading frame. Functional studies demonstrate that the Arg753Gln polymorphism, in comparison to the wild-type TLR2 gene, is significantly less responsive to bacterial peptides derived from B. burgdorferi and T. pallidum. In a septic shock population, the Arg753Gln TLR2 polymorphism occurred in 2 out of 91 septic patients. More importantly, both of the subjects with the TLR2 Arg753Gln polymorphism had staphylococcal infections. These findings suggest that a mutation in the TLR2 gene may predispose individuals to lifethreatening bacterial infections.

Sepsis is the leading cause of death in intensive care units and results from a deleterious systemic host response to infection. Although initially perceived as potentially deleterious, catalytic antibodies have been proposed to participate in removal of metabolic wastes and protection against infection. Here we show that the presence in plasma of IgG endowed with serine protease-like hydrolytic activity strongly correlates with survival from sepsis. Variances of catalytic rates of IgG were greater in the case of patients with severe sepsis than healthy donors (P < 0.001), indicating that sepsis is associated with alterations in plasma levels of hydrolytic IgG. The catalytic rates of IgG from patients who survived were significantly greater than those of IgG from deceased patients (P < 0.05). The cumulative rate of survival was higher among patients exhibiting high rates of IgG-mediated hydrolysis as compared with patients with low hydrolytic rates (P < 0.05). An inverse correlation was also observed between the markers of severity of disseminated intravascular coagulation and rates of hydrolysis of patients' IgG. Furthermore, IgG from three surviving patients hydrolyzed factor VIII, one of which also hydrolyzed factor IX, suggesting that, in some patients, catalytic IgG may participate in the control of disseminated microvascular thrombosis. Our observations provide the first evidence that hydrolytic antibodies might play a role in recovery from a disease.

Delayed awakening is common among patients recovering from coma after CA. Renal insufficiency, older age, and post-resuscitation shock were independent predictors of delayed awakening. Presence of unfavorable neurological signs at 48 h after rewarming from TTM and discontinuation of sedation did not rule out recovery of consciousness in late awakeners.