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31.
Jean-Luc Fellahi Bruno Valtier Alain Beauchet Jean-Pierre Bourdarias François Jardin 《Journal canadien d'anesthésie》1999,46(5):423-428
Purpose
To compare the hemodynamic effects of medical antishock trousers (MAST) inflation in mechanically ventilated patients with normal and poor left ventricular function.Methods
Twelve patients requiring respiratory support were divided into two groups according to baseline transesophageal echocardiography (TEE) measurements: normal left ventricular dimensions and fractional area of contraction (FAC=61 ± 5%) (n=7) and dilated cardiomyopathy with reduced FAC (21 ± 1%) (n=5). All patients were studied when two successive levels of load (mild load by inflation of the leg compartment of MAST at 50 cmH2O and high load by adding the abdominal compartment of MAST inflated at 30 cmH2O) were applied. Global left ventricular systolic function was assessed on the TEE transgastric short-axis view. End-systolic wall stress (ESWS) was used as an indicator of left ventricular afterload.Results
Total respiratory, lung and chest wall compliances were reduced by 48%, 51% and 27% respectively at the high load level (P < 0.05). Whereas no hemodynamic changes occurred at mild load, the high load level produced an increase in left ventricular afterload as evidenced by concomitant increases in diastolic arterial blood pressure (66 ± 6 to 79 ± 6 mmHg,P < 0.05) and ESWS (69 ± 12 to 74 ± 12 Kdyn·cm?2·m?2,P < 0.05). In patients with dilated cardiomyopathy, this increase in afterload impaired the left ventricular systolic function and end-systolic area increased (19.0 ± 2.5 to 21.4 ± 2.9 cm2·m?2,P < 0.05) while FAC decreased (22 ± 2 to 16 ± 2%,P < 0.05). Left ventricular end-diastolic area remained unchanged during the study in both groups.Conclusion
MAST inflation impairs respiratory mechanics and global left ventricular systolic function in cardiac patients without changes in left ventricular preload. 相似文献32.
Herbert J. Geschwind Georges Boussignac Jean-Luc Dubois-Randé Robin Zelinsky Seung-Jea Tahk 《Lasers in medical science》1991,6(3):307-310
Laser angioplasty was performed in 66 patients with total occlusion of the ilio-femoral artery. The system used consisted of a pulsed dye laser operating at 480 nm, 50 mJ pulse–1, 2s pulse–1 and 5 Hz. The treatment laser was coupled into a 200m optical fibre wrapped around a coil for improved flexibility and radiopacity. The treatment laser was connected with a diagnostic laser consisting of a continuous wave helium-cadmium laser operating at 325 nm, 50 ms and 3 mW for tissue detection using fluorescence spectroscopy. The primary success rate was 82%, the complication rate was 15% without any clinical sequelae and the 18 month follow-up patency rate was 64%. Due to the narrow pilot channel created by laser angioplasty, in each case a complementary balloon angioplasty was required to restore the arterial lumen. The success rate did not depend upon the length of occlusion but was rather related to the extent of calcification. Laser angioplasty guided by spectroscopy is effective and safe in patients with totally occluded peripheral arteries in whom mechanical devices failed to cross the obstruction. 相似文献
33.
Quantitative tumor apoptosis imaging using technetium-99m-HYNIC annexin V single photon emission computed tomography. 总被引:9,自引:0,他引:9
Christophe van de Wiele Christophe Lahorte Hubert Vermeersch D Loose Kris Mervillie Neil D Steinmetz Jean-Luc Vanderheyden Claude A Cuvelier Guido Slegers Rudi A Dierck 《Journal of clinical oncology》2003,21(18):3483-3487
PURPOSE: Radiolabeled annexin V may allow for repetitive and selective in vivo identification of apoptotic cell death without the need for invasive biopsy. This study reports on the relationship between quantitative technetium-99m- (99mTc-) 6-hydrazinonicotinic (HYNIC) radiolabeled annexin V tumor uptake, and the number of tumor apoptotic cells derived from histologic analysis. PATIENTS AND METHODS: Twenty patients (18 men, two women) suspected of primary (n = 19) or recurrent (n = 1) head and neck carcinoma were included. All patients underwent a spiral computed tomography (CT) scan, 99mTc-HYNIC annexin V tomography, and subsequent surgical resection of the suspected primary or recurrent tumor. Quantitative 99mTc-HYNIC annexin V uptake in tumor lesions divided by the tumor volume, derived from CT, was related to the number of apoptotic cells per tumor high-power field derived from terminal deoxynucleotidyl transferase-mediated deoxyuridine triphosphate-biotin nick end-labeling (TUNEL) assays performed on sectioned tumor slices. RESULTS: Diagnosis was primary head and neck tumor in 18 patients, lymph node involvement of a cancer of unknown primary origin in one patient, and the absence of recurrence in one patient. Mean percentage absolute tumor uptake of the injected dose per cubic centimeter tumor volume derived from tomographic images was 0.0003% (standard deviation [SD], 0.0004%) at 1 hour postinjection (PI) and 0.0001% (SD, 0.0000%) at 5 to 6 hours PI (P =.012). Quantitative 99mTc-HYNIC annexin V tumor uptake correlated well with the number of apoptotic cells if only tumor samples with no or minimal amounts of necrosis were considered. CONCLUSION: In the absence of necrosis, absolute 99mTc-HYNIC annexin V tumor uptake values correlate well with the number of apoptotic cells derived from TUNEL assays. 相似文献
34.
Laurence Grard Margaux Garzaro Venicia Ferrer Marion Malphettes Claire Fieschi Jean-Luc Garnier Nicolas Just Agathe Masseau Constance Delaugerre Jacques Izopet Eric Oksenhendler Florence Abravanel 《Trasfusione del sangue》2022,20(6):516
BackgroundIn a context of secondary immunodeficiency, hepatitis E virus (HEV) infection can be responsible for chronic liver disease.Materials and methodsWe investigated HEV infection in patients with primary immunodeficiency treated (or not) with immunoglobulin (Ig) replacement therapy (IgRT) in France, a country with a high seroprevalence of HEV. In a nationwide study of individuals with primary immunodeficiency, 533 patients (349 and 184 receiving IgRT or not, respectively) were tested for HEV RNA and anti-HEV antibodies. In addition, 23 batches of five different commercially available immunoglobulin preparations were screened for anti-HEV IgG.ResultsThree of the 533 patients displayed markers of a recent HEV infection (HEV RNA in one case, and anti-HEV IgG and IgM in two) but no evidence of chronic liver disease. The overall seroprevalence of HEV was 50% (266 out of 533), with values of 68% and 16% in patients receiving IgRT or not, respectively (p<0.001). Anti-HEV IgG were detected in all batches of immunoglobulin preparations, although the titer varied from 3 to 127 IU/g IgG. Seroconversion was observed in 15 of the 22 (68%) patients tested before and after IgRT.DiscussionNo cases of chronic HEV-related disease were detected among patients with primary immunodeficiency and hypogammaglobulinemia, whether they received IgRT or not. This confirms that patients with primary immunodeficiency have a low risk of chronic infection despite a seroprevalence close to that observed in the French general population and that IgRT, which confers a high HEV seroprevalence, might play a key role in protection against chronic infection. 相似文献
35.
Bouchra Asbani Yaovi Gagou Said Ben Moumen Jean-Luc Dellis Abdelilah Lahmar MBarek Amjoud Daoud Mezzane Mimoun El Marssi Brigita Rozic Zdravko Kutnjak 《Materials》2022,15(15)
Ferroelectric property that induces electrocaloric effect was investigated in Ba(GexTi1−x)O3 ceramics, known as BTGx. X-ray diffraction analysis shows pure perovskite phases in tetragonal symmetry compatible with the P4mm (No. 99) space group. Dielectric permittivity exhibits first-order ferroelectric-paraelectric phase transition, confirmed by specific heat measurements, similar to that observed in BaTiO3 (BTO) crystal. Curie temperature varies weakly as a function of Ge-content. Using the direct and indirect method, we confirmed that the adiabatic temperature change ΔT reached its higher value of 0.9 K under 8 kV/cm for the composition BTG6, corresponding to an electrocaloric responsivity ΔT/ΔE of 1.13 × 10−6 K.m/V. Such electrocaloric responsivity significantly exceeds those obtained so far in other barium titanate-based lead-free electrocaloric ceramic materials. Energy storage investigations show promising results: stored energy density of ~17 mJ/cm3 and an energy efficiency of ~88% in the composition BTG5. These results classify the studied materials as candidates for cooling devices and energy storage applications. 相似文献
36.
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
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