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991.
Becker S Laffont S Vitry F Rolland Y Lecloirec J Boucher E Raoul JL Herry JY Bourguet P Garin E 《Nuclear medicine communications》2008,29(9):815-825
OBJECTIVE: Vectorized internal radiation therapy using lipiodol-labelled with iodine-131 (131 I-lipiodol) is an effective treatment for inoperable hepatocellular carcinomas. However, few dosimetric data are available based on this approach. We have developed a dosimetric protocol based on scintiscan imaging and that is designed to calculate the tumoural absorbed dose during the treatment of hepatocarcinoma by 131 I-lipiodol. METHODS: This concept was developed on a gamma-camera coupled to a computed tomography scanner. It integrates corrections for attenuation phenomena, scattering and dead time. The tumoural absorbed dose calculation was carried out according to the Medical Internal Radiation Dose Committee formalism. This protocol was applied to a series of 41 patients in the framework of a retrospective study. RESULTS: The mean tumoural absorbed dose with the first treatment is 248 Gy (+/-176), as opposed to 152 Gy (+/-122) during the second. We highlighted a correlation between the tumoural absorbed dose, calculated in tomographic mode, and the morphological response to the first treatment (P=0.0071). Moreover, a tumoural absorbed dose of 280 Gy seems to be an effective absorbed dose threshold in our population. Above this absorbed dose, 84% of the patients are responders after the first treatment, whereas no responses are recorded below this threshold. CONCLUSION: These results are promising because, for the first time, they allow us to predict the effectiveness of a treatment by 131 I-lipiodol. They are required to be validated on a broader exploratory trial, including a dosimetric study of the critical organs, so an individualized dosimetry can be defined for each patient. 相似文献
992.
Violaine Piquet Cédric Luczak Fabien Seiler Jordan Monaury Alexandre Martini Anthony B. Ward Jean-Michel Gracies Damien Motavasseli 《Archives of physical medicine and rehabilitation》2021,102(6):1067-1074
ObjectiveTo determine the benefits associated with brief inpatient rehabilitation for coronavirus 2019 (COVID-19) patients.DesignRetrospective chart review.SettingA newly created specialized rehabilitation unit in a tertiary care medical center.ParticipantsConsecutive sample of patients (N=100) with COVID-19 infection admitted to rehabilitation.InterventionInpatient rehabilitation for postacute care COVID-19 patients.Main Outcome MeasuresMeasurements at admission and discharge comprised a Barthel Activities of Daily Living Index (including baseline value before COVID-19 infection), time to perform 10 sit-to-stands with associated cardiorespiratory changes, and grip strength (dynamometry). Correlations between these outcomes and the time spent in the intensive care unit (ICU) were explored.ResultsUpon admission to rehabilitation, 66% of the patients were men, the age was 66±22 years, mean delay from symptom onset was 20.4±10.0 days, body mass index was 26.0±5.4 kg/m2, 49% had hypertension, 29% had diabetes, and 26% had more than 50% pulmonary damage on computed tomographic scans. The mean length of rehabilitation stay was 9.8±5.6 days. From admission to discharge, the Barthel index increased from 77.3±26.7 to 88.8±24.5 (P<.001), without recovering baseline values (94.5±16.2; P<.001). There was a 37% improvement in sit-to-stand frequency (0.27±0.16 to 0.37±0.16 Hz; P<.001), a 13% decrease in post-test respiratory rate (30.7±12.6 to 26.6±6.1; P=.03), and a 15% increase in grip strength (18.1±9.2 to 20.9±8.9 kg; P<.001). At both admission and discharge, Barthel score correlated with grip strength (ρ=0.39-0.66; P<.01), which negatively correlated with time spent in the ICU (ρ=–0.57 to –0.49; P<.05).ConclusionsInpatient rehabilitation for COVID-19 patients was associated with substantial motor, respiratory, and functional improvement, especially in severe cases, although there remained mild persistent autonomy loss upon discharge. After acute stages, COVID-19, primarily a respiratory disease, might convert into a motor impairment correlated with the time spent in intensive care. 相似文献
993.
Renard JF Julémont F de Leval X Pirotte B 《Anti-cancer agents in medicinal chemistry》2006,6(3):233-237
Non-steroidal anti-inflammatory drugs (NSAIDs), which are known to be cyclooxygenase (COX) inhibitors, have been reported to exert anti-proliferative and pro-apoptotic effects on a variety of cancer cells. Since the COX-2 isoform was found to be overexpressed in a many human cancers, a particular attention was paid on the possible use of selective COX-2 inhibitors in cancer chemoprevention. The present review focuses on the state of the art in cancer research developed with COX-2 preferential/selective inhibitors belonging to the family of N-arylmethanesulfonamides, in particular nimesulide and NS-398. 相似文献
994.
Carine Signoret Etienne Gaudrain Fabien Perrin 《The European journal of neuroscience》2013,37(5):777-785
Recent human behavioral studies have shown semantic and/or lexical processing for stimuli presented below the auditory perception threshold. Here, we investigated electroencephalographic responses to words, pseudo‐words and complex sounds, in conditions where phonological and lexical categorizations were behaviorally successful (categorized stimuli) or unsuccessful (uncategorized stimuli). Data showed a greater decrease in low‐beta power at left‐hemisphere temporal electrodes for categorized non‐lexical sounds (complex sounds and pseudo‐words) than for categorized lexical sounds (words), consistent with the signature of a failure in lexical access. Similar differences between lexical and non‐lexical sounds were observed for uncategorized stimuli, although these stimuli did not yield evoked potentials or theta activity. The results of the present study suggest that behaviorally uncategorized stimuli were processed at the lexical level, and provide evidence of the neural bases of the results observed in previous behavioral studies investigating auditory perception in the absence of stimulus awareness. 相似文献
995.
Lagente V Planquois JM Leclerc O Schmidlin F Bertrand CP 《Clinical and experimental pharmacology & physiology》2008,35(5-6):601-605
1. It was proposed previously that oxidative stress is a main component of the inflammatory process in chronic obstructive pulmonary disease (COPD). Thus, in the present study, we investigated the inflammatory response in mice deficient for the p47(phox) subunit of NADPH oxidase (p47 KO) exposed to cigarette smoke (CS). 2. Exposure of mice to CS elicited an increase in the number of macrophages and neutrophils and levels of interleukin (IL)-6, keratinocyte-derived chemokine (KC/CXCL1) and monocyte chemoattractant protein-1 (MCP1/CCL2) in bronchoalveolar lavage fluid (BALF), which were lower in p47 KO mice compared with control mice. In contrast, 24 h after lipopolysaccharide (LPS) exposure, the number of macrophages and neutrophils, as well as KC/CXCL1 levels, in BALF was significantly greater in p47 KO mice compared with control mice. 3. The present study has shown that airway inflammation is decreased in p47 KO mice after exposure to CS, but not LPS, suggesting that oxidative stress is involved in the pathogenesis of airway inflammation associated with COPD. 相似文献
996.
Nadja Van Camp Raphael Boisgard Bertrand Kuhnast Benoit Thézé Thomas Viel Marie-Claude Grégoire Fabien Chauveau Hervé Boutin Andrew Katsifis Frédéric Dollé Bertrand Tavitian 《European journal of nuclear medicine and molecular imaging》2010,37(5):962-972
Purpose
The key role of neuroinflammation in acute and chronic neurological disorders has stimulated the search for specific radiotracers targeting the peripheral benzodiazepine receptor (PBR)/18 kDa translocator protein (TSPO), a hallmark of neuroinflammation. Here we evaluate the new radiotracer for positron emission tomography (PET) [18F]PBR111 in a rodent model of acute inflammation and compare it with [11C]CLINME, an 11C-labelled tracer of the same chemical family, and with the isoquinolinic carboxamide [11C]PK11195.Methods
We studied radiometabolites by HPLC, in vitro binding by autoradiography and in vivo brain kinetics as well as in vivo specificity of binding using PET imaging.Results
We show that this radiotracer has a high in vitro specificity for PBR/TSPO versus central benzodiazepine receptors, as reflected by the drastic reduction of its binding to target tissue by addition of PK11195 or PBR111, while addition of flumazenil does not affect binding. Only intact [18F]PBR111 is detected in brain up to 60 min after i.v. injection, and PET imaging shows an increased uptake in the lesion as compared to the contralateral side as early as 6 min after injection. Administration of an excess of PK11195 and PBR111, 20 min after [18F]PBR111 administration, induces a rapid and complete displacement of [18F]PBR111 binding from the lesion. Modelling of the PET data using the simplified reference tissue model showed increased binding potential (BP) in comparison to [11C]PK11195.Conclusion
[18F]PBR111 is a metabolically stable tracer with a high specific in vitro and in vivo binding to TSPO. In addition, considering the longer half-life of 18F over 11C, these results support [18F]PBR111 as a promising PET tracer of the PBR/TSPO for neuroinflammation imaging. 相似文献997.
Candice L. Wilshire Shu-Ching Chang Christopher R. Gilbert Jason A. Akulian Mohammed K. AlSarraj Rachelle Asciak Benjamin T. Bevill Kevin R. Davidson Ashley Delgado Horiana B. Grosu Felix J.F. Herth Hans J. Lee Justin E. Lewis Fabien Maldonado David E. Ost Nicholas J. Pastis Najib M. Rahman Chakravarthy B. Reddy Jed A. Gorden 《Chest》2021,159(6):2483-2487
998.
999.
Vignes M Maurice T Lanté F Nedjar M Thethi K Guiramand J Récasens M 《Brain research》2006,1110(1):102-115
Naturally occurring polyphenols are potent antioxidants. Some of these compounds are also ligands for the GABA(A) receptor benzodiazepine site. This feature endows them with sedative properties. Here, the anxiolytic activity of the green tea polyphenol (-)-epigallocatechin gallate (EGCG) was investigated after acute administration in mice, using behavioral tests (elevated plus-maze and passive avoidance tests) and by electrophysiology on cultured hippocampal neurons. Patch-clamp experiments revealed that EGCG (1-10 muM) had no effect on GABA currents. However, EGCG reversed GABA(A) receptor negative modulator methyl beta-carboline-3-carboxylate (beta-CCM) inhibition on GABA currents in a concentration dependent manner. This was also observed at the level of synaptic GABA(A) receptors by recording spontaneous inhibitory synaptic transmission. In addition, EGCG consistently inhibited spontaneous excitatory synaptic transmission. Behavioral tests indicated that EGCG exerted both anxiolytic and amnesic effects just like the benzodiazepine drug, chlordiazepoxide. Indeed, EGCG in a dose-dependent manner both increased the time spent in open arms of the plus-maze and decreased the step-down latency in the passive avoidance test. GABA(A) negative modulator beta-CCM antagonized EGCG-induced amnesia. Finally, state-dependent learning was observable after chlordiazepoxide and EGCG administration using a modified passive avoidance procedure. Optimal retention was observed only when animals were trained and tested in the same state (veh-veh or drug-drug) and significant retrieval alteration was observed in different states (veh-drug or drug-veh). Moreover, EGCG and chlordiazepoxide fully generalized in substitution studies, indicating that they induced indistinguishable chemical states for the brain. Therefore, our data support that EGCG can induce anxiolytic activity which could result from an interaction with GABA(A) receptors. 相似文献
1000.
Mélanie Plourde Jennifer Tremblay-Mercier Mélanie Fortier Fabien Pifferi Stephen C. Cunnane 《Nutrition (Burbank, Los Angeles County, Calif.)》2009,25(3):289-294
ObjectivesWe investigated whether a dietary supplement rich in eicosapentaenoic acid (EPA) increases fasting plasma ketones or postprandial ketone responses in healthy young and elderly subjects.MethodsTen young (22 ± 1 y old) and 10 elderly (75 ± 1 y old) subjects were recruited and participated in two identical study days, one before and one 6 wk after providing an EPA-enriched supplement (1.4 g/d of EPA and 0.2 g/d of docosahexaenoic acid). On the study days, blood samples were collected at fasting and every hour for 6 h after giving a breakfast. Fasting and postprandial plasma β-hydroxybutyrate (β-OHB), free fatty acid (FFA), triacylglycerol, glucose, and insulin responses were measured. Fatty acid profiles were assessed in fasting plasma samples before and after the EPA supplement.ResultsAfter the EPA supplement, postprandial plasma β-OHB responses decreased by 44% in the young and by 24% in the elderly subjects, in addition to 20% and 34% lower FFA responses in the young and elderly adults, respectively. β-OHB and FFAs were positively and significantly correlated in young but not in elderly subjects before and after the EPA supplement. In both groups, postprandial plasma triacylglycerols, glucose, and insulin were not significantly different after the intake of the EPA supplement. Before and after the EPA supplement, fasting plasma EPA was 50% higher in the elderly but increased by about five times in both groups after intake of the EPA supplement.ConclusionContrary to our expectations, EPA supplementation lowered postprandial β-OHB response and, in the elderly subjects, the concentration of postprandial β-OHB was not lowered after intake of the EPA supplement. 相似文献