Utilisation de cultures photomixotrophiques de cellules d'epinard : pour la selection de lignees resistantes a la streptomycine, pour l'etude de la transcription de genes plastidiaux au cours de la transformation d'amyloplastes en chloroplastes

SIGLECNRS T Bordereau / INIST-CNRS - Institut de l'Information Scientifique et TechniqueFRFranc

Hyperbaric oxygen therapy in a case of vaginal and uterine necrosis after embolization for postpartum hemorrhage

International audienc

External validation of the MRI-DRAGON score: early prediction of stroke outcome after intravenous thrombolysis.

The aim of our study was to validate in an independent cohort the MRI-DRAGON score, an adaptation of the (CT-) DRAGON score to predict 3-month outcome in acute ischemic stroke patients undergoing MRI before intravenous thrombolysis (IV-tPA).We reviewed consecutive (2009-2013) anterior circulation stroke patients treated within 4.5 hours by IV-tPA in the Lille stroke unit (France), where MRI is the first-line pretherapeutic work-up. We assessed the discrimination and calibration of the MRI-DRAGON score to predict poor 3-month outcome, defined as modified Rankin Score >2, using c-statistic and the Hosmer-Lemeshow test, respectively.We included 230 patients (mean ±SD age 70.4±16.0 years, median [IQR] baseline NIHSS 8 [5]-[14]; poor outcome in 78(34%) patients). The c-statistic was 0.81 (95%CI 0.75-0.87), and the Hosmer-Lemeshow test was not significant (p = 0.54).The MRI-DRAGON score showed good prognostic performance in the external validation cohort. It could therefore be used to inform the patient's relatives about long-term prognosis and help to identify poor responders to IV-tPA alone, who may be candidates for additional therapeutic strategies, if they are otherwise eligible for such procedures based on the institutional criteria

Brain-Targeting Form of Docosahexaenoic Acid for Experimental Stroke Treatment: MRI Evaluation and Anti-Oxidant Impact

Epidemiologic studies report cardiovascular protection conferred by omega-3 fatty acids, in particular docosahexaenoic acid (DHA). However, few experimental studies have addressed its potential in acute stroke treatment. The present study used multimodal MRI to assess in vivo the neuroprotection conferred by DHA and by a brain-targeting form of DHA-containing lysophosphatidylcholine (AceDoPC) in experimental stroke. Rats underwent intraluminal middle cerebral artery occlusion (MCAO) and were treated at reperfusion by intravenous injection of i) saline, ii) plasma from donor rats, iii) DHA or iv) AceDoPC, both solubilized in plasma. Twenty-four hours after reperfusion, animals underwent behavioral tests and were sacrificed. Multiparametric MRI (MRA, DWI, PWI, T2-WI) was performed at H0, during occlusion, and at H24, before sacrifice. Brain tissue was used for assay of F2-isoprostanes as lipid peroxidation markers. Initial lesion size and PWI/DWI mismatch were comparable in the four groups. Between H0 and H24, lesion size increased in the saline group (mean +/- s.d.: +18%+/- 20%), was stable in the plasma group (-3%+/- 29%), and decreased in the DHA (-17%+/- 15%, P=0.001 compared to saline) and AceDoPC (-34%+/- 29%, P=0.001 compared to saline) groups. Neuroscores in the AceDoPC group tended to be lower than in the other groups (P=0.07). Treatments (pooled DHA and AceDoPC groups) significantly decreased lipid peroxidation as compared to controls (pooled saline and vehicle) (P=0.03). MRI-based assessment demonstrated the neuroprotective effect of DHA in the MCAO model. Results further highlighted the therapeutic potential of engineered brain-targeting forms of omega-3 fatty acids for acute stroke treatment

Pre- and post-treatment with cyclosporine A in a rat model of transient focal cerebral ischaemia with multimodal MRI screening

International audienceBackground Irreversible damage may occur at reperfusion after sustained cerebral ischaemia. Aims We investigated the value of cyclosporine A for reducing the infarct size in a model of transient middle cerebral artery occlusion. Methods Twenty-seven Sprague-Dawley rats sustained a middle cerebral artery occlusion of one-hour. Acute multimodal Magnetic Resonance Imaging (MRI) was used during occlusion to confirm the success of surgery and measure baseline lesion size. Animals were randomly treated by: (i) intracarotid cyclosporine A (10 mg/kg) 20 mins before middle cerebral artery occlusion (pretreatment group); (ii) intracarotid cyclosporine A (10 mg/kg) immediately after reperfusion (post-treatment group); and (iii) intracarotid saline immediately after reperfusion. Results Histopathological measurements on day 1 showed a significant reduction of infarct size in the pretreatment group compared to the post-treatment (percentage values of ipsilateral hemispheres: 16 ± 5% vs. 29 ± 11%, P = 0*004) and saline groups (16 ± 5% vs. 42 ± 12%, P = 0*015). No significant difference was observed between the post-treatment and saline groups (P = 0*065). Behavioural examinations on day 1 showed no significant difference between groups. Immunohistochemistry showed a statistically significant reduction of microglial cell count in the pretreatment group compared to either saline or cyclosporine A post-treatment groups. Conclusions We conclude that intracarotid cyclosporine A is effective in reducing infarct size when given prior to ischaemia, but not when administered at reperfusion

Brain-Targeting Form of Docosahexaenoic Acid for Experimental Stroke Treatment: MRI Evaluation and Anti-Oxidant Impact

Epidemiologic studies report cardiovascular protection conferred by omega-3 fatty acids, in particular docosahexaenoic acid (DHA). However, few experimental studies have addressed its potential in acute stroke treatment. The present study used multimodal MRI to assess in vivo the neuroprotection conferred by DHA and by a brain-targeting form of DHA-containing lysophosphatidylcholine (AceDoPC) in experimental stroke. Rats underwent intraluminal middle cerebral artery occlusion (MCAO) and were treated at reperfusion by intravenous injection of i) saline, ii) plasma from donor rats, iii) DHA or iv) AceDoPC, both solubilized in plasma. Twenty-four hours after reperfusion, animals underwent behavioral tests and were sacrificed. Multiparametric MRI (MRA, DWI, PWI, T2-WI) was performed at H0, during occlusion, and at H24, before sacrifice. Brain tissue was used for assay of F2-isoprostanes as lipid peroxidation markers. Initial lesion size and PWI/DWI mismatch were comparable in the four groups. Between H0 and H24, lesion size increased in the saline group (mean +/- s.d.: +18%+/- 20%), was stable in the plasma group (-3%+/- 29%), and decreased in the DHA (-17%+/- 15%, P=0.001 compared to saline) and AceDoPC (-34%+/- 29%, P=0.001 compared to saline) groups. Neuroscores in the AceDoPC group tended to be lower than in the other groups (P=0.07). Treatments (pooled DHA and AceDoPC groups) significantly decreased lipid peroxidation as compared to controls (pooled saline and vehicle) (P=0.03). MRI-based assessment demonstrated the neuroprotective effect of DHA in the MCAO model. Results further highlighted the therapeutic potential of engineered brain-targeting forms of omega-3 fatty acids for acute stroke treatment

Location of intracranial aneurysms is the main factor associated with rupture in the ICAN population

Background and purpose: The ever-growing availability of imaging led to increasing incidentally discovered unruptured intracranial aneurysms (UIAs). We leveraged machine-learning techniques and advanced statistical methods to provide new insights into rupture intracranial aneurysm (RIA) risks

Three-month outcome according to MRI-DRAGON score.

<p>mRS: modified Rankin Scale.</p

Characteristics of the Validation and Derivation[5] cohorts.

<p>Numbers in parentheses are percentages, unless indicated. SD: standard deviation; IQR: interquartile range; IV-tPA: intravenous thrombolysis; OTT: Onset-to-treatment time; M1: M1 segment of the middle cerebral artery; mRS: Modified Rankin scale. NIHSS: National Institute of Health Stroke Scale. DWI-ASPECTS: Diffusion-weighted imaging Alberta Stroke Programme Early CT score.</p

The MRI-DRAGON Score (0–10 points).

<p>IV-tPA: intravenous thrombolysis; M1: M1 segment of the middle cerebral artery. Any proximal M1 occlusion on admission MR Angiography was considered, irrespective of the status of other arteries.</p><p>mRS: Modified Rankin scale. NIHSS: National Institute of Health Stroke Scale. DWI-ASPECTS: Diffusion-weighted imaging Alberta Stroke Programme Early CT score.</p