38 research outputs found

    Therapeutic Synergy Between Antibiotics and Pulmonary Toll-Like Receptor 5 Stimulation in Antibiotic-Sensitive or -Resistant Pneumonia

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    Bacterial infections of the respiratory tract constitute a major cause of death worldwide. Given the constant rise in bacterial resistance to antibiotics, treatment failure is increasingly frequent. In this context, innovative therapeutic strategies are urgently needed. Stimulation of innate immune cells in the respiratory tract [via activation of Toll-like receptors (TLRs)] is an attractive approach for rapidly activating the body's immune defenses against a broad spectrum of microorganisms. Previous studies of the TLR5 agonist flagellin in animal models showed that standalone TLR stimulation does not result in the effective treatment of pneumococcal respiratory infection but does significantly improve the therapeutic outcome of concomitant antibiotic treatment. Here, we investigated the antibacterial interaction between antibiotic and intranasal flagellin in a mouse model of pneumococcal respiratory infection. Using various doses of orally administered amoxicillin or systemically administered cotrimoxazole, we found that the intranasal instillation of flagellin (a dose that promotes maximal lung pro-inflammatory responses) induces synergistic rather than additive antibacterial effects against antibiotic–susceptible pneumococcus. We next set up a model of infection with pneumococcus that is resistant to multiple antibiotics in the context of influenza superinfection. Remarkably, the combination of amoxicillin and flagellin effectively treated superinfection with the amoxicillin-resistant pneumococcus since the bacterial clearance was increased by more than 100-fold compared to standalone treatments. Our results also showed that, in response to flagellin, the lung tissue generated an innate immune response even though it had been damaged by the influenza virus and pneumococcal infections. In conclusion, we demonstrated that the selective boosting of lung innate immunity is a conceptually advantageous approach for improving the effectiveness of antibiotic treatment and fighting antibiotic-resistant bacteria

    The Long Pentraxin PTX3 as a Humoral Innate Immunity Functional Player and Biomarker of Infections and Sepsis

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    The first line of defense in innate immunity is provided by cellular and humoral mediators. Pentraxins are a superfamily of phylogenetically conserved humoral mediators of innate immunity. PTX3, the first long pentraxin identified, is a soluble pattern recognition molecule rapidly produced by several cell types in response to primary pro-inflammatory signals and microbial recognition. PTX3 acts as an important mediator of innate immunity against pathogens of fungal, bacterial and viral origin, and as a regulator of inflammation, by modulating complement activation and cell extravasation, and facilitating pathogen recognition by myeloid cells. In sepsis, PTX3 plasma levels are associated with severity of the condition, patient survival, and response to therapy. In combination with other established biomarkers, PTX3 could improve stratification of sepsis patients and thus, complement the system of classification and monitoring of this disease

    Serum amyloid P component is an essential element of resistance against Aspergillus fumigatus

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    © The Author(s) 2021. Open Access. This article is licensed under a Creative Commons Attribution 4.0 International License, which permits use, sharing, adaptation, distribution and reproduction in any medium or format, as long as you give appropriate credit to the original author(s) and the source, provide a link to the Creative Commons license, and indicate if changes were made. The images or other third party material in this article are included in the article’s Creative Commons license, unless indicated otherwise in a credit line to the material. If material is not included in the article’s Creative Commons license and your intended use is not permitted by statutory regulation or exceeds the permitted use, you will need to obtain permission directly from the copyright holder. To view a copy of this license, visit http://creativecommons.org/licenses/by/4.0/.Serum amyloid P component (SAP, also known as Pentraxin 2; APCS gene) is a component of the humoral arm of innate immunity involved in resistance to bacterial infection and regulation of tissue remodeling. Here we investigate the role of SAP in antifungal resistance. Apcs-/- mice show enhanced susceptibility to A. fumigatus infection. Murine and human SAP bound conidia, activate the complement cascade and enhance phagocytosis by neutrophils. Apcs-/- mice are defective in vivo in terms of recruitment of neutrophils and phagocytosis in the lungs. Opsonic activity of SAP is dependent on the classical pathway of complement activation. In immunosuppressed mice, SAP administration protects hosts against A. fumigatus infection and death. In the context of a study of hematopoietic stem-cell transplantation, genetic variation in the human APCS gene is associated with susceptibility to invasive pulmonary aspergillosis. Thus, SAP is a fluid phase pattern recognition molecule essential for resistance against A. fumigatus.The contribution of the European Commission (ERC project PHII-669415; FP7 project 281608 TIMER; ESA/ITN, H2020-MSCA-ITN-2015-676129), Ministero dell’Istruzione, dell’Università e della Ricerca (MIUR) (project FIRB RBAP11H2R9), Associazione Italiana Ricerca sul Cancro (AIRC IG-19014 and IG-21714, AIRC 5 × 1000 −9962 and −21147), the Italian Ministry of Health, the Northern Portugal Regional Operational Programme (NORTE 2020), under the Portugal 2020 Partnership Agreement, through the European Regional Development Fund (ERDF) (NORTE-01-0145-FEDER-000013 and NORTE-01-0145-FEDER-000023), the Fundação para a Ciência e Tecnologia (FCT) (UIDB/50026/2020, UIDP/50026/2020, PTDC/SAU-SER/29635/2017, PTDC/MED-GEN/28778/2017, CEECIND/04058/2018 and CEECIND/03628/2017), the European Union’s Horizon 2020 research and innovation program under grant agreement no. 847507 and the “la Caixa” Foundation (ID 100010434) and FCT under the agreement LCF/PR/HR17/52190003 is gratefully acknowledged.info:eu-repo/semantics/publishedVersio

    Improved Survival of HIV-1-Infected Patients with Progressive Multifocal Leukoencephalopathy Receiving Early 5-Drug Combination Antiretroviral Therapy

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    Progressive multifocal leukoencephalopathy (PML), a rare devastating demyelinating disease caused by the polyomavirus JC (JCV), occurs in severely immunocompromised patients, most of whom have advanced-stage HIV infection. Despite combination antiretroviral therapy (cART), 50% of patients die within 6 months of PML onset. We conducted a multicenter, open-label pilot trial evaluating the survival benefit of a five-drug cART designed to accelerate HIV replication decay and JCV-specific immune recovery.All the patients received an optimized cART with three or more drugs for 12 months, plus the fusion inhibitor enfuvirtide during the first 6 months. The main endpoint was the one-year survival rate. A total of 28 patients were enrolled. At entry, median CD4+ T-cell count was 53 per microliter and 86% of patients had detectable plasma HIV RNA and CSF JCV DNA levels. Seven patients died, all before month 4. The one-year survival estimate was 0.75 (95% confidence interval, 0.61 to 0.93). At month 6, JCV DNA was undetectable in the CSF of 81% of survivors. At month 12, 81% of patients had undetectable plasma HIV RNA, and the median CD4+ T-cell increment was 105 per microliter. In univariate analysis, higher total and naive CD4+ T-cell counts and lower CSF JCV DNA level at baseline were associated with better survival. JCV-specific functional memory CD4+ T-cell responses, based on a proliferation assay, were detected in 4% of patients at baseline and 43% at M12 (P = 0.008).The early use of five-drug cART after PML diagnosis appears to improve survival. This is associated with recovery of anti-JCV T-cell responses and JCV clearance from CSF. A low CD4+ T-cell count (particularly naive subset) and high JCV DNA copies in CSF at PML diagnosis appear to be risk factors for death.ClinicalTrials.gov NCT00120367

    Effects of 17β-estradiol exposure in the mussel Mytilus galloprovincialis

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    4 pages, 2 figures.-- PMID: 15178065 [PubMed].-- Printed version published in issue Aug-Dec 2004.-- Issue title: "Twelfth International Symposium on Pollutant Responses in Marine Organisms" (Tampa Bay, FL, United States, May 9-13, 2003).Mussels Mytilus galloprovincialis were exposed to different concentrations of estradiol (20, 200, and 2000 ng/l) in a semi-static regime (1-day dosing intervals) for up to 7 days in an attempt to see how mussels dealt with exogenous estrogenic compounds. Sex hormone levels were determined in whole tissue. Free-estradiol was only significantly elevated at the highest exposure dose (up to 10-fold). Most of the estradiol was in the tissues as fatty acid esters (>78%), which sharply increased in a dose-dependent manner (from 4 ng/g in controls to 258 ng/g at the high exposure group). In contrast, neither free nor esterified testosterone levels showed significant differences between control and exposure groups. The results suggest the existence of mechanisms that allow mussels to maintain their hormonal status, and the important role that fatty acid esterification may play within those mechanisms. Synthesis and conjugation rates of estradiol were further investigated by measuring the activity of P450 aromatase, and palmitoyl-CoA:estradiol acyltransferase, in digestive gland microsomal fractions. Overall, the study contributes to the better knowledge of molluscan endocrinology, and defines new mechanisms of regulation of free steroid-levels in mussels.Predoctoral fellowship from the Spanish Government and partial support from EU Project BEEP (ENVK3-CT-2000-00025).Peer reviewe

    Effects of endocrine disrupters on sex steroid synthesis and metabolism pathways in fish

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    10 pages, 5 figures, 1 table.-- PMID: 15698553 [PubMed].The interactions of estrogenic (nonylphenol, dicofol, atrazine), androgenic (organotins, phthalates, fenarimol) and anti-androgenic compounds (vinclozolin, diuron, p,p′-DDE) with key enzymatic activities involved in both synthesis and metabolism of sex hormones was investigated. Carp testicular microsomes incubated in the presence of androstenedione and different xenobiotics evidenced higher sensitivity of 5α-reductase activity than 17β-hydroxysteroid dehydrogenase activity towards those chemicals. Dicofol, organotins and phthalates were among the most effective inhibitors. In contrast, ovarian synthesis of maturation-inducing hormones (20α- and 20β-hydroxysteroid dehydrogenase activities) were enhanced by nonylphenol, dicofol, fenarimol and p,p′-DDE. Metabolic clearance pathways of hormones were also affected. Fenarimol, nonylphenol and triphenyltin inhibited the glucuronidation of testosterone and estradiol at concentrations as low as 10, 50 and 100 μM, respectively. Triphenyltin, tributyltin and nonylphenol were also inhibitors of estradiol sulfation with IC50 values of 17, 18 and 41 μM. Overall, the data indicates the interaction of selected chemicals with key enzymatic pathways involved in both synthesis and metabolism of sex hormones. This interference might be one of the underlying mechanisms for the reported hormonal disrupting properties of the tested compounds, and might finally affect physiological processes such as gamete growth and maturation.This study was supported by the Spanish National Plan for Research under Project Ref. REN2002-01709/HID.Peer reviewe

    Electrodynamic Fragmentation of High Value Compound & bulk materials with potentially recoverable substances EDF-HVC ECO-INNOVERA call 2

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    Electrodynamic Fragmentation of High Value Compound & bulk materials with potentiall recoverable substances (EDF-HVC

    Electrodynamic Fragmentation of E-waste

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    Untersuchungen dazu werden in diesem Bericht am Beispiel von WEEE und speziell an Leiter-platten aufgezeigt. Die Versuche zeigen, dass EDF für verschiedenste Arten von Elektroschrott eingesetzt werden kann. Verschweisste Kompaktgeräte können zum Beispiel so weit geöffnet werden, dass die ge-wünschte Komponente freigelegt und entfernt werden kann. Leiterplatten haben die Eigenschaft, dass bei kontinuierlich steigendem Energieeintrag zuerst die aufgebrachten Komponenten abgetrennt werden, bevor die Cu-Bahnen freigelegt werden. Bei noch höherem Energieeintrag wird die Leiterplatte schlussendlich zerkleinert und vollständig zer-stört. Durch diese Entfrachtung der Leiterplatte kann ein metallreiches Konzentrat hergestellt werden
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