LPS-Induced Production of Inflammatory Mediators in the Liver of Postnatal Animals

Lipopolysaccharide (LPS) is the primary component of the outer membrane of Gram-negative bacteria and is responsible for the majority of inflammatory effects of infections from Gram-negative bacteria. To gain better understanding of the effects that postnatal age has on the inflammatory response, pups were randomly assigned to be treated with 250 µg/kg of LPS or saline at postnatal day (P) 1, P21, and P70. Two hours post stimulation, the pups were sacrificed and their livers were harvested for total RN A extraction. Relative mRNA levels of inflammatory genes and �-actin were determined using RT-PCR analysis with appropriate rat sense and antisense primers. The specific inflammatory mediators examined were toll-like receptor-4 (TLR4), cluster of differentiation 14 (CD14), myeloid differentiation factor 88 (Myd88), cytokines including interleukin (IL )-1 �. IL-6, and tumor necrosis factor (TNF)-a, and chemokines including macrophage inflammatory protein (MIP)-1 �, MIP-2, and monocyte chemotactic protein (MCP)-1. We found that the LPS-induced mRNA expression of the cytokines and chemokines examined appear to be increased as compared to the control pups. Furthermore, we showed that an activation of cytokines and chemokines in the liver exhibited age-dependency in pups treated with LPS at Pl, P21, and P70. The pattern shows an increase in relative mRNA expression of cytokines and chemokines as development progresses. Furthermore, we compared the kinetics of cytokine and chemokine induction in PI and P2 l animals. We found that that there was a delayed cytokine and chemokine induction at PI as compared to P2 l pups. Our data suggest that the hepatic innate immunity undergo significant development during early postnatal development, and the delayed inflammatory response in Pl animals may contribute to increased susceptibility of neonatal animals to infections

Retinal safety of intravitreal rtPA in healthy rats and under excitotoxic conditions.

Intravitreal recombinant tissue plasminogen activator (rtPA) is used off-label for the surgical management of submacular hemorrhage, a severe complication of neovascular age-related macular degeneration. rtPA is approved for coronary and cerebral thrombolysis. However, in ischemic stroke rtPA is known to increase excitotoxic neural cell death by interacting with the N-methyl-D-aspartate (NMDA) receptor. We therefore investigated the retinal toxicity of rtPA in healthy rats and in a model of NMDA-induced retinal excitotoxicity. First, rtPA at three different doses (2.16 µg/5 µl, 0.54 µg/5 µl, and 0.27 µg/5 µl) or vehicle (NaCl 0.9%) was injected intravitreally in healthy rat eyes. Electroretinograms (ERGs) were performed at 24 h or 7 days. Annexin V-fluorescein isothiocyanate (FITC)-labeled apoptotic retinal ganglion cells (RGCs) were counted on flatmounted retinas at 24 h or 7 days. Next, NMDA + vehicle or NMDA + rtPA (0.27 µg/5 µl) was injected intravitreally to generate excitotoxic conditions. Apoptotic annexin V-FITC-labeled RGCs and surviving Brn3a-labeled RGCs were quantified on flatmounted retinas and radial sections, 18 h after treatment. In healthy rat eyes, the number of apoptotic RGCs was statistically significantly increased 24 h after the administration of rtPA at the highest dose (2.16 µg/5 µl; p = 0.0250) but not at the lower doses of 0.54 and 0.27 µg/5 µl (p = 0.36 and p = 0.20), compared to vehicle. At day 7, there was no difference in the apoptotic RGC count between the rtPA- and vehicle-injected eyes (p = 0.70, p = 0.52, p = 0.11). ERG amplitudes and implicit times were not modified at 24 h or 7 days after injection of any tested rtPA doses, compared to the baseline. Intravitreal administration of NMDA induced RGC death, but under these excitotoxic conditions, coadministration of rtPA did not increase the number of dead RGCs (p = 0.70). Similarly, the number of surviving RGCs on the flatmounted retinas and retinal sections did not differ between the eyes injected with NMDA + vehicle and NMDA + rtPA (p = 0.59 and p = 0.67). At low clinical equivalent doses corresponding to 25 µg/0.1 ml in humans, intravitreal rtPA is not toxic for healthy rat retinas and does not enhance NMDA-induced excitotoxicity. Vitreal equivalent doses ≥200 µg/0.1 ml should be avoided in patients, due to potential RGC toxicity

Adolescents and adults with Fontan circulation:insights from the PREpArE-Fontan registry

The Patient Registry for Adolescents and Adults with Stable Fontan Circulation aims to describe a contemporary cohort of Fontan patients who could be eligible for a clinical trial investigating macitentan, an endothelin receptor antagonist. This international, non-interventional, multicentre, cross-sectional, observational registry enrolled patients with “stable” Fontan circulation ≥10 years following extra-cardiac conduit or lateral tunnel procedure. Main exclusion criteria were NYHA functional class IV, reoperation of Fontan circulation, or signs of disease worsening. Patient characteristics at enrolment are described; available data were collected during a single registration visit. Of the 266 screened patients, 254 were included in this analysis. At enrolment, median (interquartile range) age was 24 (20;30) years, 37%/63% of patients were from the USA/Europe, 54% were male, 54%/47% had undergone extra-cardiac conduit/lateral tunnel procedures, and 95% were in NYHA functional class I or II. History of arrhythmia was more common in older patients and patients with lateral tunnel; overall prevalence was 19%. Most laboratory values were within the normal range but mean creatinine clearance was abnormally low (87.7 ml/min). Angiotensin-converting enzyme inhibitors were used by 48% of patients and their use was associated with creatinine clearance <90 ml/min (p = 0.007), as was Fontan completion at an older age (p = 0.007). 53.4% of patients had clinical characteristics that could potentially meet an endothelin receptor antagonist trial’s eligibility criteria. The PREpArE-Fontan registry describes a cohort of patients who could potentially participate in an endothelin receptor antagonist trial and identified early subtle signs of Fontan failure, even in “stable” patients

Probe-based schemes to guarantee lightpath quality of transmission (QoT) in transparent optical networks

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Enhancing GMPLS signaling protocol for encompassing quality of transmission (QoT) in all-optical networks

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Modulation of NTC frequencies by Pc5 ULF pulsations : experimental test of the generation mechanism and magnetoseismology of the emitting surface

Nonthermal continuum (NTC) radiation is believed to be emitted by the conversion of an electrostatic wave into an electromagnetic one, which takes place at the Earth's magnetic equator. It is generally accepted that the frequency of the electrostatic wave at the source meets a local characteristic frequency placed in between two multiples of the electron cyclotron frequency, fce, which results in emission of a narrow band frequency element. In an event on 14 August 2003, we compare oscillations of the central frequency of distinct NTC frequency elements observed from Cluster orbiting near perigee, with simultaneous Pc5 Ultra Low Frequency (ULF) pulsations in the magnetic field observed from the same platform. The latter magnetic perturbations are interpreted as magnetohydrodynamic poloidal waves, where fundamental and second harmonic modes coexist. The NTC oscillation and the fundamental wave have similar periods, but are phase shifted by a quarter of period. From the correlation between both signals, and the proximity of the NTC source (localized via triangulation) with Cluster, we infer that the poloidal perturbations are spatially uniform between the source and the satellites. From the phase shift between signals, we conclude that the electrostatic wave which converts into NTC is mainly governed by the plasma density, affected by movements of the magnetic field lines. Furthermore, we demonstrate that the observations can be used to perform a magnetoseismology of the emitting surface. The results show a steepening of the plasmapause density profile near the satellites, which can be responsible for the generation of NTC emission

An integrated view on monitoring and compensation for dynamic optical networks: from management to physical layer

A vertical perspective, ranging from management and routing to physical layer options, concerning dynamic network monitoring and compensation of impairments (M&C), is given. Feasibility, reliability, and performance improvements on reconfigurable transparent networks are expected to arise from the consolidated assessment of network management and control specifications, as a more accurate evaluation of available M&C techniques. In the network layer, physical parameters aware algorithms are foreseen to pursue reliable network performance. In the physical layer, some new M&C methods were developed and rating of the state-of-the-art reported in literature is given. Optical monitoring implementation and viability is discussed.Publicad

Characterization of the Molecular Determinants of Primary HIV-1 Vpr Proteins: Impact of the Q65R and R77Q Substitutions on Vpr Functions

Although HIV-1 Vpr displays several functions in vitro, limited information exists concerning their relevance during infection. Here, we characterized Vpr variants isolated from a rapid and a long-term non-progressor (LTNP). Interestingly, vpr alleles isolated from longitudinal samples of the LTNP revealed a dominant sequence that subsequently led to diversity similar to that observed in the progressor patient. Most of primary Vpr proteins accumulated at the nuclear envelope and interacted with host-cell partners of Vpr. They displayed cytostatic and proapoptotic activities, although a LTNP allele, harboring the Q65R substitution, failed to bind the DCAF1 subunit of the Cul4a/DDB1 E3 ligase and was inactive. This Q65R substitution correlated with impairment of Vpr docking at the nuclear envelope, raising the possibility of a functional link between this property and the Vpr cytostatic activity. In contradiction with published results, the R77Q substitution, found in LTNP alleles, did not influence Vpr proapoptotic activity