95 research outputs found
Identification and characterization of an endogenous chemotactic ligand specific for FPRL2
Chemotaxis of dendritic cells (DCs) and monocytes is a key step in the initiation of an adequate immune response. Formyl peptide receptor (FPR) and FPR-like receptor (FPRL)1, two G proteinâcoupled receptors belonging to the FPR family, play an essential role in host defense mechanisms against bacterial infection and in the regulation of inflammatory reactions. FPRL2, the third member of this structural family of chemoattractant receptors, is characterized by its specific expression on monocytes and DCs. Here, we present the isolation from a spleen extract and the functional characterization of F2L, a novel chemoattractant peptide acting specifically through FPRL2. F2L is an acetylated amino-terminal peptide derived from the cleavage of the human heme-binding protein, an intracellular tetrapyrolle-binding protein. The peptide binds and activates FPRL2 in the low nanomolar range, which triggers intracellular calcium release, inhibition of cAMP accumulation, and phosphorylation of extracellular signalâregulated kinase 1/2 mitogen-activated protein kinases through the Gi class of heterotrimeric G proteins. When tested on monocytes and monocyte-derived DCs, F2L promotes calcium mobilization and chemotaxis. Therefore, F2L appears as a new natural chemoattractant peptide for DCs and monocytes, and the first potent and specific agonist of FPRL2
Comparing story reading and video watching as two distinct forms of vicarious contact: An experimental intervention among elementary school children
Research has shown that vicarious contact, that is observing an interaction between ingroup and outgroup members, can improve intergroup relations. Although vicarious contact has been operationalized in different ways, mainly via story reading or video watching, an experimental comparison of these different strategies is still missing. We conducted a school intervention with the aim of comparing the two most used forms of vicarious contact, namely story reading and video watching. Elementary schoolchildren without disabilities (N = 292) were assigned to one of three different conditions: reading a story; watching a video; control. In the two vicarious contact conditions, participants read or watched the story of a child with disability becoming friends with children without disabilities; in the control condition, participants only completed the dependent measures. Results revealed that, in general, both vicarious contact conditions were equally effective in improving outgroup attitudes and behavioural intentions. In addition, they operated with the same strength through the same underlying processes (IOS, ingroup norms). We discuss theoretical and practical implications in the context of vicarious contact as a prejudice-reduction intervention
Prevalence and trends of markers of hepatitis B virus, hepatitis C virus and human Immunodeficiency virus in Argentine blood donors
BACKGROUND: Transfusion-transmitted infections are a major problem associated with blood transfusion. The aim of this study was to determine prevalence and trends of HBV, HCV and HIV in blood donors in Argentina. METHODS: A retrospective study was carried out in blood donors of 27 transfusion centers covering the whole country over a period of eight years (2004-2011). Serologic screening assays for HBsAg, anti-HBc, anti-HCV, and anti-HIV were performed in all centers and nucleic acid amplification testing (NAT) was performed in 2 out of the 27 centers. RESULTS: The 2,595,852 samples tested nationwide from 2004 to 2011 showed that the prevalence of HBsAg decreased from 0.336% to 0.198% (p < 0.0001), that of anti-HBc from 2.391% to 2.007% (p < 0.0001), that of anti-HCV from 0.721% to 0.460%, (p < 0.0001) and that of anti-HIV from 0.208% to 0.200 (p = 0.075). The prevalence of HBV, HCV and HIV was unevenly distributed among the different regions of the country. Two out of 74,838 screening- negative samples were positive in NAT assays (1 HIV-RNA and 1 HCV-RNA); moreover, HBV-DNA, HCV-RNA and HIV-RNA were detected in 60.29, 24.54 and 66.67% of screening-positive samples of the corresponding assays. As regards donors age, positive HBV-DNA and HCV-RNA donors were significantly older than healthy donors (46.6, 50.5 and 39.5 y respectively, p < 0.001). CONCLUSIONS: Argentina has a low prevalence of HBsAg, anti-HCV and anti-HIV in blood donors, with a decreasing trend for HBsAg, anti-HBc and anti-HCV but not for anti-HIV over the last 8 years. The uneven distribution of transfusion-transmitted infections prevalence among the different regions of the country highlights the need to implement regional awareness campaigns and prevention. The discrepancy between samples testing positive for screening assays and negative for NAT assays highlights the problem of blood donors who test repeatedly reactive in screening assays but are not confirmed as positive upon further testing. The uneven distribution of age between healthy donors and NAT-positive donors could be related to changes in risks of these pathogens in the general population and might be attributed to a longer exposure to transmission risk factors in elderly people.Fil: Flichman, Diego Martin. Universidad de Buenos Aires. Facultad de Farmacia y BioquĂmica. Departamento de MicrobiologĂa, InmunologĂa y BiotecnologĂa. CĂĄtedra de VirologĂa; Argentina. Consejo Nacional de Investigaciones CientĂficas y TĂ©cnicas; ArgentinaFil: Blejer, Jorgelina L.. FundaciĂłn Hemocentro; ArgentinaFil: Livellara, Beatriz I.. Hospital Italiano; ArgentinaFil: RĂ©, Viviana Elizabeth. Universidad Nacional de Cordoba. Facultad de Medicina. Instituto de VirologĂa; Argentina. Consejo Nacional de Investigaciones CientĂficas y TĂ©cnicas; ArgentinaFil: Bartoli, Sonia. Centro regional de Hemoterapia Jujuy; ArgentinaFil: Bustos, Juan A.. Banco de sangre San Jorge; ArgentinaFil: Ansola, Claudia P.. Provincia de Mendoza. Servicio de Hemoterapia; ArgentinaFil: Hidalgo, Susana. Hospital Dr. Enrique Vera Barros; ArgentinaFil: Cerda, MartĂn E.. Hospital Dr. Lucio Molas; ArgentinaFil: Levin, Alicia E.. Provincia de Mendoza. Servicio de Hemoterapia; ArgentinaFil: Huenul, Adriana. Hospital ArtĂ©mides Zatti; ArgentinaFil: Riboldi, Victoria. Hospital Regional RĂo Gallegos; ArgentinaFil: Treviño, Elena M. C.. Universidad Nacional de CĂłrdoba; ArgentinaFil: Salamone, Horacio J.. FundaciĂłn Favaloro; ArgentinaFil: Nuñez, Felix A.. Hospital Italiano; ArgentinaFil: FernĂĄndez, Robert J.. FundaciĂłn Hemocentro; ArgentinaFil: Reybaud, Juan F.. FundaciĂłn Favaloro; ArgentinaFil: Campos, Rodolfo Hector. Universidad de Buenos Aires. Facultad de Farmacia y BioquĂmica. Departamento de MicrobiologĂa, InmunologĂa y BiotecnologĂa. CĂĄtedra de VirologĂa; Argentina. Consejo Nacional de Investigaciones CientĂficas y TĂ©cnicas; Argentin
Low-dose oral imatinib in the treatment of systemic sclerosis interstitial lung disease unresponsive to cyclophosphamide: a phase II pilot study
Introduction: Pulmonary involvement represents a major cause of death of systemic sclerosis (SSc) patients. Recent data suggest that tyrosine kinase inhibitors, such as imatinib, may be a therapeutic option for SSc patients. However, preliminary published clinical trials were inconclusive about imatinib efficacy and showed side effects. The purpose of this study was to verify efficacy and tolerability of low-dose imatinib on interstitial lung disease in a cohort of SSc patients unresponsive to cyclophosphamide therapy.Methods: Thirty consecutive SSc patients with active pulmonary involvement, unresponsive to cyclophosphamide, were treated with imatinib 200 mg/day for 6 months followed by a 6-month follow-up. A "good response" was defined as an increase of forced vital capacity (FVC) by more of 15% and/or increase of diffusing capacity of carbon monoxide (DLCO) > 15% and PaO2 > 90% of initial value and high-resolution computed tomography (HRCT)-scan pattern unchanged or improved.Results: Twenty-six patients completed the study. Three patients died and one patient was lost to follow-up. Four patients (15.32%) had a good response, 7 worsened and 15 had a stabilized lung disease. Overall, 19 (73.07%) patients had an improved or stabilized lung disease. After a 6-month follow-up, 12 (54.5%) of the 22 patients showed an improved or stabilized lung disease.Conclusions: Lung function was stabilized in a large proportion of patients unresponsive to cyclophosphamide therapy and a beneficial outcome emerged from the analysis of HRCT lung scans. There was no significant improvement of skin involvement, and the low dose was well tolerated. These data provide useful suggestions to design future randomized clinical trials for SSc therapeutics
Modeling of GERDA Phase II data
The GERmanium Detector Array (GERDA) experiment at the Gran Sasso underground
laboratory (LNGS) of INFN is searching for neutrinoless double-beta
() decay of Ge. The technological challenge of GERDA is
to operate in a "background-free" regime in the region of interest (ROI) after
analysis cuts for the full 100kgyr target exposure of the
experiment. A careful modeling and decomposition of the full-range energy
spectrum is essential to predict the shape and composition of events in the ROI
around for the search, to extract a precise
measurement of the half-life of the double-beta decay mode with neutrinos
() and in order to identify the location of residual
impurities. The latter will permit future experiments to build strategies in
order to further lower the background and achieve even better sensitivities. In
this article the background decomposition prior to analysis cuts is presented
for GERDA Phase II. The background model fit yields a flat spectrum in the ROI
with a background index (BI) of cts/(kgkeVyr) for the enriched BEGe data set and
cts/(kgkeVyr) for the
enriched coaxial data set. These values are similar to the one of Gerda Phase I
despite a much larger number of detectors and hence radioactive hardware
components
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Modeling of GERDA Phase II data
The GERmanium Detector Array (Gerda) experiment at the Gran Sasso underground laboratory (LNGS) of INFN is searching for neutrinoless double-beta (0ÎœÎČÎČ) decay of 76Ge. The technological challenge of Gerda is to operate in a âbackground-freeâ regime in the region of interest (ROI) after analysis cuts for the full 100 kg·yr target exposure of the experiment. A careful modeling and decomposition of the full-range energy spectrum is essential to predict the shape and composition of events in the ROI around QÎČÎČ for the 0ÎœÎČÎČ search, to extract a precise measurement of the half-life of the double-beta decay mode with neutrinos (2ÎœÎČÎČ) and in order to identify the location of residual impurities. The latter will permit future experiments to build strategies in order to further lower the background and achieve even better sensitivities. In this article the background decomposition prior to analysis cuts is presented for Gerda Phase II. The background model fit yields a flat spectrum in the ROI with a background index (BI) of 16.04+0.78â0.85â
10â3 cts/(keV·kg·yr) for the enriched BEGe data set and 14.68+0.47â0.52â
10â3 cts/(keV·kg·yr) for the enriched coaxial data set. These values are similar to the one of Phase I despite a much larger number of detectors and hence radioactive hardware components
Tumor-associated myeloid cells: new understandings on their metabolic regulation and their influence in cancer immunotherapy
Tumor-associated myeloid cells (TAMCs), mainly represented by tumor-associated macrophages (TAMs) and myeloid-derived suppressor cells (MDSCs), can promote tumor growth directly, by favouring tumor cell proliferation and survival, and indirectly, by creating an immunosuppressive microenvironment. Myeloid cells are characterized by an extreme phenotypical and functional plasticity. Immunometabolism is now emerging as a crucial aspect of TAMCs skewing towards pro-tumoral activities. The metabolic re-education of myeloid cells is a new strategy to boost their anti-tumor effector functions. Several anticancer therapies targeting TAMCs are already under investigation. Nowadays, the hot topic of cancer immunotherapy is represented by immune checkpoint inhibitors. These drugs unrestrain T cell-mediated tumor elimination by removing suppressive signals delivered by tumor-associated cells. The efficacy of immune checkpoint blockade can be enhanced using coordinated strategies to counteract the TAMCs-dependent impairment of immune adaptive responses. In the first part of the review, we will describe the association between metabolic reprogramming and TAMCs biological activities. In the second part, we will illustrate the potential of combination therapies associating TAMC-targeting drugs with immune checkpoint inhibitors
Molecular and epigenetic basis of macrophage polarized activation
Macrophages are unique cells for origin, heterogeneity and plasticity. At steady state most of macrophages are derived from fetal sources and maintained in adulthood through self-renewing. Despite sharing common progenitors, a remarkable heterogeneity characterized tissue-resident macrophages indicating that local signals educate them to express organ-specific functions. Macrophages are extremely plastic: chromatin landscape and transcriptional programs can be dynamically re-shaped in response to microenvironmental changes. Owing to their ductility, macrophages are crucial orchestrators of both initiation and resolution of immune responses and key supporters of tissue development and functions in homeostatic and pathological conditions. Herein, we describe current understanding of heterogeneity and plasticity of macrophages using the M1-M2 dichotomy as operationally useful simplification of polarized activation. We focused on the complex network of signaling cascades, metabolic pathways, transcription factors, and epigenetic changes that control macrophage activation. In particular, this network was addressed in sepsis, as a paradigm of a pathological condition determining dynamic macrophage reprogramming
Effects of COVID-19 Lockdown on the Emotional and Behavioral Profiles of Preschool Italian Children with and without Familial Risk for Neurodevelopmental Disorders
The effects of COVID-19 containment measures on the emotional and behavioral development of preschoolers are not clear. We investigated them within an ongoing longitudinal project including typically developing children (TD) and children at high familial risk for neurodevelopmental disorders (HR-NDD) who were potentially more vulnerable. The study included ninety children aged 2â6 years (TD = 48; HR-NDD = 42). Before the emergency phase (T0), all children received a clinical assessment, including the parent questionnaire Child Behavior Checklist for Ages 1.5â5 (CBCL 1.5â5). The same questionnaire was filled out again during the emergency (T1), together with an ad-hoc questionnaire investigating environmental factors characterizing the specific period. Changes in the CBCL profiles between T0 and T1 were evaluated. Overall, irrespective of familial risk, the average T-scores on specific CBCL scales at T1 were higher than at T0. Associations emerged between delta scores reflecting worsening scores on specific CBCL scales and clinical and environmental factors. Our results confirmed the negative impact of the lockdown on preschool childrenâs emotional/behavioral profiles, and highlight the need for strategic approaches in the age range of 2â6 years, especially for more susceptible children owing to environmental factors and pre-existing emotional problems
Engagement of BDCA-2 blocks TRAIL-mediated cytotoxic activity of plasmacytoid dendritic cells
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