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991.
992.
Effect of AY 9944 and chlorpromazine on Concanavalin A-induced stimulation of human lymphocytes 总被引:2,自引:0,他引:2
V Barbu J C Mazière F Maindrault C Mazière C Rampini C Roux J Polonovski 《Biochemical pharmacology》1987,36(3):353-356
Amphiphilic molecules AY 9944 and chlorpromazine (CPZ) inhibited DNA synthesis in Concanavalin A-stimulated lymphocytes in a dose-dependent manner. While AY 9944 strongly decreased 7-dehydrocholesterol conversion to cholesterol, CPZ did not significantly affect this reaction. Moreover, the inhibitory effect of AY 9944 and CPZ on DNA synthesis took place in the presence of cholesterol in the culture medium. These findings suggest that the mechanism of inhibition of DNA synthesis by AY 9944 or CPZ is not related to endogenous cholesterol synthesis or exogenous cholesterol supply. Results are discussed in relation to the amphiphilic properties of AY 9944 and CPZ and to the interaction of these drugs with membranes or other intracellular targets such as calmodulin. 相似文献
993.
Marie-Laure Paillère Martinot Jean-Luc Martinot Damien Ringuenet André Galinowski Thierry Gallarda Frank Bellivier Jean-Pascal Lefaucheur Hervé Lemaitre Eric Artiges 《Neuropsychopharmacology》2011,36(13):2710-2719
Neuroimaging studies of patients with treatment-resistant depression (TRD) have reported abnormalities in the frontal and temporal regions. We sought to determine whether metabolism in these regions might be related to response to repetitive transcranial magnetic stimulation (TMS) in patients with TRD. Magnetic resonance images and baseline resting-state cerebral glucose uptake index (gluMI) obtained using 18F-fluorodeoxyglucose positron emission tomography were analyzed in TRD patients who had participated in a double-blind, randomized, sham-controlled trial of prefrontal 10 Hz TMS. Among the patients randomized to active TMS, 17 responders, defined as having 50% depression score decrease, and 14 nonresponders were investigated for prestimulation glucose metabolism and compared with 39 healthy subjects using a voxel-based analysis. In nonresponders relative to responders, gluMI was lower in left lateral orbitofrontal cortex (OFC), and higher in left amygdala and uncinate fasciculus. OFC and amygdala gluMI negatively correlated in nonresponders, positively correlated in responders, and did not correlate in healthy subjects. Relative to healthy subjects, both responders and nonresponders displayed lower gluMI in right dorsolateral prefrontal (DLPFC), right anterior cingulate (ACC), and left ventrolateral prefrontal cortices. Additionally, nonresponders had lower gluMI in left DLPFC, ACC, left and right insula, and higher gluMI in left amygdala and uncus. Hypometabolisms were partly explained by gray matter reductions, whereas hypermetabolisms were unrelated to structural changes. The findings suggest that different patterns of frontal–temporal–limbic abnormalities may distinguish responders and nonresponders to prefrontal magnetic stimulation. Both preserved OFC volume and amygdala metabolism might precondition response to TMS. 相似文献
994.
Seyed Heydar Mosavi Mirak Seyedmehdi Sharifian Fatemeh Esmaeili Khalil Saraei Neda Asasian-Kolur Bahram Haddadi Christian Jordan Michael Harasek 《Materials》2022,15(13)
Titanium-pillared clay (Ti-PILC), as one of the most suitable types of porous adsorbents/(photo)catalysts, was prepared from a local type of Iranian clay and titanium isopropoxide. The production process was optimized by changing three operating parameters, including the clay suspension concentration (in the range of 0.5–10% w/v), the H+/Ti ratio (2–8 mol/mol), and the calcination temperature (300–700 °C). The largest specific surface area for the Ti-PILC was about 164 m2/g under the clay suspension of 0.5% w/v, H+/Ti = 6, with a surface area 273% larger than that of the raw clay. The surface areas obtained from more concentrated clay suspensions were, however, comparable (159 m2/g for 3% w/v clay and H+/Ti = 4). An increase in the calcination temperature has a negative effect on the porous texture of Ti-PILC, but based on modeling with artificial neural networks, its contribution was only 7%. Clay suspension and H+/Ti ratio play a role of 56 and 37% of the specific surface area. The presence of rutile phase, and in some cases anatase phase of TiO2 crystals was detected. FTIR and SEM investigations of Ti-PILCs produced under different operating parameters were analyzed. 相似文献
995.
Christopher Sie Ravi Kant Christian Peter Andreas Muschaweckh Monika Pfaller Lucy Nirschl Helena Domínguez Moreno Tereza Chadimov Gildas Lepennetier Tanja Kuhlmann Rupert
llinger Thomas Engleitner Roland Rad Thomas Korn 《The Journal of experimental medicine》2022,219(8)
In certain instances, Th17 responses are associated with severe immunopathology. T cell–intrinsic mechanisms that restrict pathogenic effector functions have been described for type 1 and 2 responses but are less well studied for Th17 cells. Here, we report a cell-intrinsic feedback mechanism that controls the pathogenicity of Th17 cells. Th17 cells produce IL-24, which prompts them to secrete IL-10. The IL-10–inducing function of IL-24 is independent of the cell surface receptor of IL-24 on Th17 cells. Rather, IL-24 is recruited to the inner mitochondrial membrane, where it interacts with the NADH dehydrogenase (ubiquinone) 1 α subcomplex subunit 13 (also known as Grim19), a constituent of complex I of the respiratory chain. Together, Grim19 and IL-24 promote the accumulation of STAT3 in the mitochondrial compartment. We propose that IL-24–guided mitochondrial STAT3 constitutes a rheostat to blunt extensive STAT3 deflections in the nucleus, which might then contribute to a robust IL-10 response in Th17 cells and a restriction of immunopathology in experimental autoimmune encephalomyelitis. 相似文献
996.
Emilie Brard Christoph Rllig Sarah Bertoli Arnaud Pigneux Suzanne Tavitian Michael Kramer Hubert Serve Martin Bornhuser Uwe Platzbecker Carsten Müller-Tidow Claudia D. Baldus David Martínez-Cuadrn Josefina Serrano Pilar Martínez-Snchez Eduardo Rodríguez Arbolí Cristina Gil Juan Bergua Teresa Bernal Adolfo de la Fuente Burguera Eric Delabesse Audrey Bidet Pierre-Yves Dumas Pau Montesinos Christian Rcher 《Blood cancer journal》2022,12(7)
In a context of therapeutic revolution in older adults with AML, it is becoming increasingly important to select patients for the various treatment options by taking account of short-term efficacy and toxicity as well as long-term survival. Here, the data from three European registries for 1,199 AML patients aged 70 years or older treated with intensive chemotherapy were used to develop a prognostic scoring system. The median follow-up was 50.8 months. In the training set of 636 patients, age, performance status, secondary AML, leukocytosis, and cytogenetics, as well as NPM1 mutations (without FLT3-ITD), were all significantly associated with overall survival, albeit not to the same degree. These factors were used to develop a score that predicts long-term overall survival. Three risk-groups were identified: a lower, intermediate and higher-risk score with predicted 5-year overall survival (OS) probabilities of ≥12% (n = 283, 51%; median OS = 18 months), 3–12% (n = 226, 41%; median OS = 9 months) and <3% (n = 47, 8%; median OS = 3 months), respectively. This scoring system was also significantly associated with complete remission, early death and relapse-free survival; performed similarly in the external validation cohort (n = 563) and showed a lower false-positive rate than previously published scores. The European Scoring System ≥70, easy for routine calculation, predicts long-term survival in older AML patients considered for intensive chemotherapy.Subject terms: Acute myeloid leukaemia, Risk factors 相似文献
997.
Ulrich Hegerl Roland Mergl Christian Sander Jens Dietzel Istvan Bitter Koen Demyttenaere Ricardo Gusmão Ana González-Pinto Iñaki Zorrilla Adriana García Alocén Victor Perez Sola Eduard Vieta Georg Juckel Ulrich S. Zimmermann Michael Bauer Pascal Sienaert Sónia Quintão Marc-Andreas Edel Michael Kluge 《European neuropsychopharmacology》2018,28(1):185-194
Based on many clinical and preclinical findings the ‘vigilance regulation model of mania’ postulates that an unstable regulation of wakefulness is a pathogenetic factor in both mania and Attention Deficit Hyperactivity Disorder (ADHD) and induces hyperactivity and sensation seeking as an autoregulatory attempt to stabilize wakefulness. Accordingly, stimulant medications with their vigilance stabilizing properties could have rapid antimanic effects similar to their beneficial effects in ADHD. The MEMAP study – a multi-center, double-blind, placebo-controlled and randomized clinical trial (RCT) – assessed the antimanic efficacy and safety of a 2.5-day treatment with methylphenidate (20–40 mg/day). Of 157 screened patients with acute mania, 42 were randomly assigned to receive 20–40 mg per day of methylphenidate in one or two applications, or placebo. The primary outcome was the change in Young Mania Rating Scale (YMRS) sum scores from baseline to day 2.5 in the methylphenidate group compared to the placebo group. A group sequential design was chosen to justify early RCT termination based on efficacy or futility at an interim analysis after inclusion of 40 patients. In the interim analysis, the change from baseline in the YMRS total score at day 2.5 was not significantly different between both groups (F(1,37)=0.23; p=0.64). Thus, futility was declared for methylphenidate and the RCT was stopped. In summary, although methylphenidate was well tolerated and safe in the full analysis set, it failed to show efficacy in the treatment of acute mania. Trial registration: clinicaltrials.gov (URL: http://www.clinicaltrials.gov; registration number: NCT01541605). 相似文献
998.
Val S Stéphanie V Martinon L Laurent M Cachier H Hélène C Yahyaoui A Abderrazak Y Marfaing H Hélène M Baeza-Squiban A Armelle BS 《Inhalation toxicology》2011,23(11):627-640
The increased levels of fine particles in the atmosphere are suspected of aggravating cardiopulmonary diseases, but the determinants of particle toxicity are poorly understood. This work aims at studying the role of composition and size in the toxicity of size-segregated particulate matter (PM) collected at different sites on human bronchial epithelial cells. PM were sampled at a traffic urban site (Urb S) and a rural site (Rur S) during the pesticide-spreading period. Ultrafine (UF), fine (F), and coarse (C) PM were characterized by their shape and chemical composition. Whatever the site, the finest PM (UF and F) induced the mRNA expression of CYP1A1, a biomarker of polyaromatic hydrocarbons (PAH) exposure, NQO-1 and heme HO-1, two antioxidant responsive element-driven genes; and two effect biomarkers, GM-CSF, a proinflammatory cytokine and amphiregulin (AR), a growth factor. C PM have a low or no effect. Interestingly, AR is more strongly induced by rural PM at the same mass exposure. These discrepancies suggest involvement of PM chemical composition: rural PM bearing the characteristics of aged aerosols with a high content of water-soluble components, and PM at urban kerbside sites containing mainly water-insoluble components. To conclude, we provide evidence that the finest PM fractions, whatever their origin, are more prone to induce exposure and effect biomarkers. The AR differential expression suggests a source-dependent effect requiring further investigation because of the role of this growth factor in airway remodeling, a characteristic feature of chronic lung respiratory diseases exacerbated by particulate pollution. 相似文献
999.
Mathias Moser Sarah Dine Dominique Vrel Loïc Perrire Rmy Pirs-Brazuna Herv Couque Frdric Bernard 《Materials》2022,15(15)
This work concerns the sintering of tungsten-based (i.e WMoTaNb) high entropy alloy (HEA) powders using the spark plasma sintering (SPS) technique and their mechanical properties. The synthesis was performed by a self-propagating high-temperature synthesis (SHS) type reaction in which the mixture of metallic oxides (WO3, MoO3 …) is reduced by magnesium. For this, a specific reactor has been developed. Different conditions including the addition of a moderator were tested. These powders are then densified by SPS technology which allows for keeping the initial microstructure of the powder. The optimization of sintering conditions was performed with the objective to control simultaneously the chemical composition, the grain growth and the densification stages. 相似文献
1000.
Frank Vitinius Martin Hellmich Annalena Matthies Fabian Bornkessel Heiner Burghart Christian Albus Karl-Bernd Huettenbrink Julia Vent 《European archives of oto-rhino-laryngology》2014,271(9):2443-2454
It has been suggested that certain odorants positively affect mood, but this has not yet been scientifically tested in humans. The aim of the current study was to demonstrate the feasibility of a new odorant applicator and to assess the effects of nocturnal intermittent rose odorant application on mood, and quality of sleep and dreams in depressed female inpatients. We hypothesised that mood as primary outcome will improve. Twenty-seven normosmic, 18- to 49-year-old female, depressed inpatients were investigated in a randomised, placebo-controlled, crossover study. Exclusion criteria were rhinitis, hyp- or anosmia. During sleep, an interval-controlled, inspiration-triggered applicator added rose concentrate to the inspirated air. There were three consecutive nights of each odorant and placebo application and a wash-out phase. Patients completed standardised questionnaires on mood, dreams, and sleep quality. Four patients dropped out (n = 1: non-compliance in filling in the questionnaires, n = 3: intolerance of nasal tube). Otherwise, this novel odorant applicator was well tolerated. Application of the odorant showed no significant mood differences between rose and placebo, however, some subdomains of sleep quality and mood showed a positive trend towards improvement by rose application. The feasibility of this new device and of nasal tubes could be shown. Odorant application is well tolerated. It may have a positive influence on quality of mood and sleep in depressed patients. A longer application phase is planned to obtain convincing evidence for our hypothesis. 相似文献