Search results for "purpura"
showing 10 items of 88 documents
Ecological implications of purple sea urchin (Heliocidaris crassispina, Agassiz, 1864) enhancement on the coastal benthic food web: evidence from sta…
2020
A responsible approach to marine stock enhancement is an effective approach to restore fishery resources. While the release strategy of target species has been well investigated, the impacts on local ecological equilibrium and habitat qualities have only been poorly considered. In the present study, we evaluated how the macro-benthic food web in Daya Bay was affected by purple sea urchin (Heliocidaris crassispina (Agassiz, 1864) stock enhancement using stable isotope analyses (δ13C and δ15N). Our results indicated that the distribution of local species and trophic diversity were influenced to a certain degree by release of purple sea urchins and changes in the feeding habit of the urchins w…
Warmer temperatures reduce the influence of an important keystone predator
2017
Predator–prey interactions may be strongly influenced by temperature variations in marine ecosystems. Consequently, climate change may alter the importance of predators with repercussions for ecosystem functioning and structure. In North-eastern Pacific kelp forests, the starfish Pycnopodia helianthoides is known to be an important predator of the purple sea urchin Strongylocentrotus purpuratus. Here we investigated the influence of water temperature on this predator–prey interaction by: (i) assessing the spatial distribution and temporal dynamics of both species across a temperature gradient in the northern Channel Islands, California, and (ii) investigating how the feeding rate of P. heli…
Altered distribution and function of splenic innate lymphoid cells in adult chronic immune thrombocytopenia
2018
IF 7.607; International audience; Innate lymphoid cells (ILCs) have been characterized as innate immune cells capable to modulate the immune response in the mucosae. Human ILCs have been rarely described in secondary lymphoid organs except in tonsils. Moreover, their function and phenotype in human secondary lymphoid organs during autoimmune diseases have never been studied. We took advantage of splenectomy as a treatment of immune thrombocytopenia (ITP) to describe and compare splenic ILC from 18 ITP patients to 11 controls. We first confirmed that ILC3 represented the most abundant ILC subset in human non-inflamed spleens, accounting for 90% of total ILC, and that they were mostly constit…
Incidence, Diagnosis, and Outcome of Acquired Thrombotic Thrombocytopenic Purpura (aTTP): A Nationwide Survey By the Spanish Apheresis Group
2019
Introduction: Acquired thrombotic thrombocytopenic purpura (aTTP) is a rare disease characterized by a severe deficiency of the enzymatic activity of ADAMTS13 caused by autoantibodies, with an incidence of 3-4 x106inhabitants per year according to the few published data available. Accurate estimates of the incidence of aTTP are important to assess the resources required for current treatments and to anticipate the need to develop new treatments. The aim of this study was to determine the actualincidence of aTTP in Spain, as well as its diagnosis, management, and associated complications. Material and methods:A cross-sectional surveywascarried out among hematologists working in Spanish hospi…
Redefining outcomes in immune TTP: an international working group consensus report
2021
Abstract Immune-mediated thrombotic thrombocytopenic purpura (iTTP) is a potentially fatal thrombotic microangiopathy caused by autoantibody-mediated severe deficiency of ADAMTS13. Standardized definitions of response, exacerbation, remission, and relapse were initially proposed in 2003 and modified by the International Working Group for TTP in 2017. These definitions, which have been widely used in clinical practice and research, are based primarily on the platelet count and are benchmarked against the timing of discontinuation of therapeutic plasma exchange (TPE). They do not incorporate ADAMTS13 activity or the temporizing effects on the platelet count of caplacizumab, a novel anti–von W…
Platelet-activating factor type activity in plasma from patients with septicemia and other diseases
1991
The purpose of the present study was to determine whether increased levels of platelet-activating factor (PAF) type activity can be detected in plasma from patients with septicemia and other diseases. A level of PAF below 0.5 ng/mL of plasma was considered normal. We found that plasma from a patient with adverse anaphylactoidic reaction to intravenous analgetics contained 2.1 ng PAF/mL. In seven patients with septicemia, including urosepsis, endocarditis and peritonitis, and with positive blood culture, increased plasma PAF levels (1-20 ng PAF/mL) were observed. Other patients with clinical indications of septicemia had negative blood cultures and/or increased levels of C-reactive protein (…
Protein�A immunoadsorption therapy for refractory, mitomycin�C?associated thrombotic microangiopathy
2007
BACKGROUND: Mitomycin C–associated thrombotic microangiopathy (TMA) has a poor prognosis with limited therapeutic options. Most patients die within 4 months of diagnosis due to pulmonary or renal failure. Here, a patient resistant to total plasma exchange (TPE) and immunosuppressive therapy with glucocorticoids, rituximab, vincristine, and splenectomy who was successfully treated with protein A immunoadsorption is described. CASE REPORT: A 29-year-old woman developed a TMA after chemotherapy with mitomycin C. She presented with thrombocytopenia, pulmonary edema, hemolytic anemia with presence of schistocytes, and renal failure. Immediate TPE (>120 times) and immunosuppressive therapy with g…
Successful treatment of resistant thrombotic thrombocytopenic purpura/hemolytic uremic syndrome with autologous peripheral blood stem and progenitor …
1999
The first-line treatment of thrombotic thrombocytopenic purpura-hemolytic uremic syndrome (TTP-HUS syndrome) induces a response and survival rate of approximately 85%, even if a considerable number of patients relapse; nevertheless, a number of these patients are resistant to conventional management. Immunoablation followed by stem cell transplantation has been shown to be capable of inducing remissions in a large spectrum of experimental autoimmune disorders. We report here the case of a 20-year-old male patient with the TTP-HUS syndrome who was resistant to conventional treatment and was transplanted with autologous immunoselected CD34+ PBPC after conditioning with cyclosphosphamide, anti…
Preferential splenic CD8+ T-cell activation in rituximab-nonresponder patients with immune thrombocytopenia
2013
The pathogenic role of B cells in immune thrombocytopenia (ITP) has justified the therapeutic use of anti-CD20 antibodies such as rituximab (RTX). However, 60% of ITP patients do not respond to RTX. To decipher the mechanisms implicated in the failure of RTX, and because the spleen plays a well-recognized role in ITP pathogenesis, 12 spleens from ITP patients who had been nonresponders to RTX therapy were compared with 11 spleens from RTX-untreated ITP patients and 9 controls. We here demonstrate that in RTX-nonresponder ITP patients, preferential Th1 and Tc1 T lymphocyte polarizations occur, associated with an increase in splenic effector memory CD8(+) T-cell frequency. Moreover, in the RT…