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Insaf Salem Fourati Anne-Julie Grenier élyse Jolette Natacha Merindol Philippe Ovetchkine Hugo Soudeyns 《Journal of visualized experiments : JoVE》2014,(89)
Varicella zoster virus (VZV) is a significant cause of morbidity and mortality following umbilical cord blood transplantation (UCBT). For this reason, antiherpetic prophylaxis is administrated systematically to pediatric UCBT recipients to prevent complications associated with VZV infection, but there is no strong, evidence based consensus that defines its optimal duration. Because T cell mediated immunity is responsible for the control of VZV infection, assessing the reconstitution of VZV specific T cell responses following UCBT could provide indications as to whether prophylaxis should be maintained or can be discontinued. To this end, a VZV specific gamma interferon (IFN-γ) enzyme-linked immunospot (ELISpot) assay was developed to characterize IFN-γ production by T lymphocytes in response to in vitro stimulation with irradiated live attenuated VZV vaccine. This assay provides a rapid, reproducible and sensitive measurement of VZV specific cell mediated immunity suitable for monitoring the reconstitution of VZV specific immunity in a clinical setting and assessing immune responsiveness to VZV antigens. 相似文献
514.
The hypothesis tested is that Fe administration leads to a response in rat brain modulating the effects of later oxidative challenges such as chlorpromazine (CPZ) administration. Either a single dose (acute Fe overload) or 6 doses every second day (sub-chronic Fe overload) of 500 or 50 mg Fe-dextran/kg, respectively, were injected intraperitoneally (ip) to rats. A single dose of 10 mg CPZ/kg was injected ip 8 h after Fe treatment. DNA integrity was evaluated by quantitative PCR, lipid radical (LR·) generation rate by electron paramagnetic resonance (EPR), and catalase (CAT) activity by UV spectrophotometry in isolated brains. The maximum increase in total Fe brain was detected after 6 or 2 h in the acute and sub-chronic Fe overload model, respectively. Mitochondrial and nuclear DNA integrity decreased after acute Fe overload at the time of maximal Fe content; the decrease in DNA integrity was lower after sub-chronic than after acute Fe overload. CPZ administration increased LR· generation rate in control rat brain after 1 and 2 h; however, CPZ administration after acute or sub-chronic Fe overload did not affect LR· generation rate. CPZ treatment did not affect CAT activity after 1–4 h neither in control rats nor in acute Fe-overloaded rats. However, CPZ administration to rats treated sub-chronically with Fe showed increased brain CAT activity after 2 or 4 h, as compared to control values. Fe supplementation prevented brain damage in both acute and sub-chronic models of Fe overload by selectively activating antioxidant pathways. 相似文献
515.
Anne-Pauline Bellanger Houssein Gbaguidi-Haore Natacha Tatoyan Ana Berceanu Emeline Scherer Laurence Millon 《Folia microbiologica》2018,63(6):757-761
Galactomannan antigen (GM) testing has been used for decades to screen immunocompromised patients for invasive aspergillosis (IA). Recent publications suggested that using a higher cut-off value than 0.5 in bronchoalveolar lavage fluid (BALF) could be more discriminant for hematology patients. We retrospectively analyzed the values of GM in BALF over 7 years (from 2010 to 2016). Performance indicators of the GM in BALF, according to three different cut-off values (0.5, 0.8, 1.5), were calculated using Stata 14.1. IA classification for hematology patients was based on European Organization for Research and Treatment of Cancer/Mycoses Study Group (EORTC/MSG) criteria, as defined in 2008. A number of 716 GM were performed on BALF from 2010 to 2016 (597 patients) and 66 were positive (>?0.5). Among these 597 patients, 27 IA were diagnosed, 13 with a positive GM in BALF, 9 with a negative GM in BALF, and 5 unclassified IA (ICU patients). The analysis of performance indicators, based on our local data, did not demonstrate any significant difference using a higher cut-off value of GM in BALF. This result may be explained by the local recruitment of patients and by pre-analytic variations during BALF realization. 相似文献
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Tim Kamber Theo H. M. Smits Fabio Rezzonico Brion Duffy 《Trees - Structure and Function》2012,26(1):227-238
The bacterial plant pathogen Erwinia amylovora causes fire blight, a major disease threat to pome fruit production worldwide with further impact on a wide-range of Rosaceae species. Important factors contributing to the development of the disease were discovered in the last decades. Comparative
genomics of the genera Erwinia and Pantoea is coming into focus with the recent availability of complete genome sequences. Insights from comparative genomics now position
us to answer fundamental questions regarding the evolution of E. amylovora as a successful pathogen and the critical elements for biocontrol activity of Pantoea spp. This trove of new data promises to reveal novel determinants and to understand interactive pathways for virulence, host
range and ecological fitness. The ultimate aim is now to apply genomics and identify the pathogen Achilles heels and antagonist
mechanisms of action as targets for designing innovative control strategies for fire blight. 相似文献
518.
D E Brion M Donnadieu C Liapi J Argente M C Tonon P Garnier J C Job 《Hormone research》1986,24(2-3):116-120
Plasma growth hormone releasing factor (GHRH) was measured by RIA in the plasma of 41 children with constitutionally short stature. Basal plasma GHRH was 51 +/- 10 pg/ml. L-Dopa induced a 2-fold increase in circulating GHRH 30-45 min before the elevation of GH. A positive correlation (p less than 0.005) was found between the peak of GH and GHRH during the dopaminergic stimulus. On the opposite, the secretion of GH induced by amino acids or clonidine is not preceded by an elevation of plasma GHRH. When a release of GH appeared after the insertion of the venous catheter alone, probably due to the stress, it was preceded by a rise of plasma GHRH. In four sleeping adolescents during the night no relationship was found between the peaks of plasma GHRH and the peaks of GH secretion. These results suggest that the various stimulations of GH secretion used for investigations of a short stature do not act in the same way at the hypothalamo-pituitary level. 相似文献
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Estela Natacha Brandt Busanello Ângela Zanatta Anelise Miotti Tonin Carolina Maso Viegas Carmen Regla Vargas Guilhian Leipnitz César Augusto João Ribeiro Moacir Wajner 《Journal of bioenergetics and biomembranes》2013,45(1-2):137-144
Refsum disease is an autosomal recessive disorder of peroxisomal metabolism biochemically characterized by highly elevated concentrations of phytanic acid (Phyt) in a variety of tissues including the cerebellum. Reduction of plasma Phyt levels by dietary restriction intake ameliorates ataxia, a common clinical manifestation of this disorder, suggesting a neurotoxic role for this branched-chain fatty acid. Therefore, considering that the underlying mechanisms of cerebellum damage in Refsum disease are poorly known, in the present study we tested the effects of Phyt on important parameters of bioenergetics, such as the activities of the respiratory chain complexes I to IV, creatine kinase and Na+, K+- ATPase in cerebellum preparations from young rats. The activities of complexes I, II, I–III and II–III and Na+, K+- ATPase were markedly inhibited (65–85 %) in a dose-dependent manner by Phyt. In contrast, creatine kinase and complex IV activities were not altered by this fatty acid. Therefore, it is presumed that impairment of the electron flow through the respiratory chain and inhibition of Na+, K+- ATPase that is crucial for synaptic function may be involved in the pathophysiology of the cerebellar abnormalities manifested as ataxia in Refsum disease and in other peroxisomal disorders in which brain Phyt accumulates. 相似文献