147 research outputs found

    Costimulatory molecule expression on leukocytes from mice with experimental autoimmune encephalomyelitis treated with IFN-beta

    Get PDF
    Interferon-beta (IFN-beta) is of benefit in the treatment of multiple sclerosis (MS) and experimental autoimmune encephalomyelitis (EAE), but the mechanisms by which it exerts this beneficial effect remain uncertain. The present data demonstrate that IFN-beta therapy impairs the proliferative response to concanavalin A (ConA) and myelin basic protein (MBP), decreases expression of the CD80 molecule on leukocytes of treated mice, and may thereby impede the Th1 cell activation-promoting anergy in EAE. Moreover, IFN-beta therapy increases expression of the CTLA4 molecule, which induces a counterregulatory Th2 response. The reduction of CD80 expression with concomitant increase of CTLA4 expression alters the course of EAE and may be useful as a monitor in therapy with IFN-beta.23629329

    Diminished myelin-specific T cell activation associated with increase in CTLA4 and Fas molecules in multiple sclerosis patients treated with IFN-beta

    Get PDF
    Multiple sclerosis (MS) is a chronic inflammatory disease of the white matter of the central nervous system (CNS) characterized by focal areas of demyelination. Interferon-beta (IFN-beta) provides an effective treatment that lessens the frequency and severity of exacerbations in relapsing-remitting multiple sclerosis (RRMS), but the mechanisms by which IFN-beta is efficient remain uncertain. The data presented here demonstrate that IFN-beta impairs the proliferative response to myelin basic protein (MBP) and myelin, as well as increasing the expression of the CTLA4 intracellular molecule. Moreover, this treatment increases the expression of surface Fas molecules and of the soluble form of these molecules. Our hypothesis is that the increase in Fas and CTLA4 molecules in MS patients may lead to lymphocyte apoptosis, which suggests possible mechanisms underlying the therapeutic response to IFN-beta.271086587

    Electrochemical Characterization of Clean Shape-Controlled Pt Nanoparticles Prepared in Presence of Oleylamine/Oleic Acid

    Get PDF
    A collection of shape-controlled Pt nanoparticles has been prepared using two different and previously described methodologies, both using oleylamine/oleic acid as capping material/solvent. A new decontamination protocol is presented to effectively clean the surface of the different nanoparticles thus allowing a full exposure of their surface area and consequently to make the most of their surface structure dependent reactivity. Subsequently, the clean shape-controlled Pt nanoparticles have been electrochemically characterized and their electrocatalytic properties evaluated towards some surface structure reactions of interest. The results indicate that the full characterization of the surface structure cannot be done exclusively by the available microscopy techniques, since it is very difficult to determine the presence of surface defects. Additional surface characterization probes, such as those provided by electrochemical surface sensitive reactions, have been used to assess the surface structure of the samples.This work has been financially supported by the MICINN (Feder) of Spain and Generalitat Valencia through Projects CTQ2013-44083-P and PROMETEOII/2014/013, respectively

    Ecoepidemiology and biology of Eratyrus mucronatus Stål, 1859 (Hemiptera: Reduviidae: Triatominae), a sylvatic vector of Chagas disease in the Brazilian Amazon

    Get PDF
    Introduction Eratyrus mucronatus Stål, 1859 is a wild triatomine vector of Trypanosoma cruzi Chagas, 1909. However, little is known regarding the biology and ecoepidemiology of this triatomine in the Brazilian Amazon. The present study describes the biology of E. mucronatus grown under laboratory conditions and the epidemiological aspects of its natural breeding sites. Methods Five colonies were monitored in the field for 3 years. Temperature and humidity measurements were taken in the mornings and afternoons at the natural breeding sites, and the behavior and distribution of the nymphs and adults were observed in the wild colony. We also monitored the life cycle under controlled laboratory conditions. Results Some factors that were considered decisive for the establishment of these colonies were present at all of the colonies studied in the field. These factors included an active termite nest, a vertebrate for repast, and dry and shaded substrates with temperatures of 24-28°C and with humidity of 80-90%. A generation was developed in 274 days under these microclimatic conditions in the laboratory. Conclusions The climatic variables described in the field indicate that these environmental parameters have a limiting effect on the dispersal and colonization of E. mucronatus to new environments. In addition, the long period of development to adulthood demonstrates that only one generation can develop per year even under the more favorable laboratory conditions

    Biased-corrected richness estimates for the Amazonian tree flora

    Get PDF
    Amazonian forests are extraordinarily diverse, but the estimated species richness is very much debated. Here, we apply an ensemble of parametric estimators and a novel technique that includes conspecific spatial aggregation to an extended database of forest plots with up-to-date taxonomy. We show that the species abundance distribution of Amazonia is best approximated by a logseries with aggregated individuals, where aggregation increases with rarity. By averaging several methods to estimate total richness, we confirm that over 15,000 tree species are expected to occur in Amazonia. We also show that using ten times the number of plots would result in an increase to just ~50% of those 15,000 estimated species. To get a more complete sample of all tree species, rigorous field campaigns may be needed but the number of trees in Amazonia will remain an estimate for years to come

    Atrasentan and renal events in patients with type 2 diabetes and chronic kidney disease (SONAR): a double-blind, randomised, placebo-controlled trial

    Get PDF
    Background: Short-term treatment for people with type 2 diabetes using a low dose of the selective endothelin A receptor antagonist atrasentan reduces albuminuria without causing significant sodium retention. We report the long-term effects of treatment with atrasentan on major renal outcomes. Methods: We did this double-blind, randomised, placebo-controlled trial at 689 sites in 41 countries. We enrolled adults aged 18–85 years with type 2 diabetes, estimated glomerular filtration rate (eGFR)25–75 mL/min per 1·73 m 2 of body surface area, and a urine albumin-to-creatinine ratio (UACR)of 300–5000 mg/g who had received maximum labelled or tolerated renin–angiotensin system inhibition for at least 4 weeks. Participants were given atrasentan 0·75 mg orally daily during an enrichment period before random group assignment. Those with a UACR decrease of at least 30% with no substantial fluid retention during the enrichment period (responders)were included in the double-blind treatment period. Responders were randomly assigned to receive either atrasentan 0·75 mg orally daily or placebo. All patients and investigators were masked to treatment assignment. The primary endpoint was a composite of doubling of serum creatinine (sustained for ≥30 days)or end-stage kidney disease (eGFR <15 mL/min per 1·73 m 2 sustained for ≥90 days, chronic dialysis for ≥90 days, kidney transplantation, or death from kidney failure)in the intention-to-treat population of all responders. Safety was assessed in all patients who received at least one dose of their assigned study treatment. The study is registered with ClinicalTrials.gov, number NCT01858532. Findings: Between May 17, 2013, and July 13, 2017, 11 087 patients were screened; 5117 entered the enrichment period, and 4711 completed the enrichment period. Of these, 2648 patients were responders and were randomly assigned to the atrasentan group (n=1325)or placebo group (n=1323). Median follow-up was 2·2 years (IQR 1·4–2·9). 79 (6·0%)of 1325 patients in the atrasentan group and 105 (7·9%)of 1323 in the placebo group had a primary composite renal endpoint event (hazard ratio [HR]0·65 [95% CI 0·49–0·88]; p=0·0047). Fluid retention and anaemia adverse events, which have been previously attributed to endothelin receptor antagonists, were more frequent in the atrasentan group than in the placebo group. Hospital admission for heart failure occurred in 47 (3·5%)of 1325 patients in the atrasentan group and 34 (2·6%)of 1323 patients in the placebo group (HR 1·33 [95% CI 0·85–2·07]; p=0·208). 58 (4·4%)patients in the atrasentan group and 52 (3·9%)in the placebo group died (HR 1·09 [95% CI 0·75–1·59]; p=0·65). Interpretation: Atrasentan reduced the risk of renal events in patients with diabetes and chronic kidney disease who were selected to optimise efficacy and safety. These data support a potential role for selective endothelin receptor antagonists in protecting renal function in patients with type 2 diabetes at high risk of developing end-stage kidney disease. Funding: AbbVie
    corecore