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1.
Thierry Patrice David Olivier Ludovic Bourre 《Journal of environmental pathology, toxicology and oncology》2006,25(1-2):467-485
Photodynamic therapy (PDT) is based on the selective light activation of an exogenously given drug to patients. PDT acts mainly on cell membranes either of neovascular endothelial cells or of cancer cells leading to cancer cell death. Six drugs are now marketed based on clinical assays in various indications, which showed a clear cost efficiency as compared to other classical procedures. PDT is easy to handle and can be performed in medical installations fitting the conditions of health care in developing countries. Its cost effectiveness could represent an appropriate solution to the increasing number of cancers of various origin. However despite all the clinical results now available, PDT development remains slow. The reasons for this situation include cost of development, intellectual property, and competition between pharmaceutical companies. 相似文献
2.
Chukwuka C Okafor Hana Haleem-Smith Patrice Laqueriere Paul A Manner Rocky S Tuan 《Journal of orthopaedic research》2006,24(3):461-473
Continual loading and articulation cycles undergone by metallic (e.g., titanium) alloy arthroplasty prostheses lead to liberation of a large number of metallic debris particulates, which have long been implicated as a primary cause of periprosthetic osteolysis and postarthroplasty aseptic implant loosening. Long-term stability of total joint replacement prostheses relies on proper integration between implant biomaterial and osseous tissue, and factors that interfere with this integration are likely to cause osteolysis. Because multipotent mesenchymal stem cells (MSCs) located adjacent to the implant have an osteoprogenitor function and are critical contributors to osseous tissue integrity, when their functions or activities are compromised, osteolysis will most likely occur. To date, it is not certain or sufficiently confirmed whether MSCs endocytose titanium particles, and if so, whether particulate endocytosis has any effect on cellular responses to wear debris. This study seeks to clarify the phenomenon of titanium endocytosis by human MSCs (hMSCs), and investigates the influence of endocytosis on their activities. hMSCs incubated with commercially pure titanium particles exhibited internalized particles, as observed by scanning electron microscopy and confocal laser scanning microscopy, with time-dependent reduction in the number of extracellular particles. Particulate endocytosis was associated with reduced rates of cellular proliferation and cell-substrate adhesion, suppressed osteogenic differentiation, and increased rate of apoptosis. These cellular effects of exposure to titanium particles were reduced when endocytosis was inhibited by treatment with cytochalasin D, and no significant effect was seen when hMSCs were treated only with conditioned medium obtained from particulate-treated cells. These findings strongly suggest that the biological responses of hMSCs to wear debris are triggered primarily by the direct endocytosis of titanium particulates, and not mediated by secreted soluble factors. In this manner, therapeutical approaches that suppress particle endocytosis could reduce the bioreactivity of hMSCs to particulates, and enhance long-term orthopedic implant prognosis by minimizing wear-debris periprosthethic osteolysis. 相似文献
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Ventilation imaging of the lung: Comparison of hyperpolarized helium-3 MR imaging with Xe-133 scintigraphy 总被引:1,自引:0,他引:1
Talissa A. Altes MD Patrice K. Rehm MD Frank Harrell PhD Michael Salerno PhD Thomas M. Daniel MD Eduard E. de Lange MD 《Academic radiology》2004,11(7):729-734
RATIONALE AND OBJECTIVES: To compare hyperpolarized helium-3 (HHe) magnetic resonance imaging (MRI) of the lung with standard Xe-133 lung ventilation scintigraphy. MATERIALS AND METHODS: We performed a retrospective review of 15 subjects who underwent HHe MRI and Xe-133 lung ventilation imaging. Coronal MRI sections were acquired after a single inhalation of HHe gas, and standard posterior planar lung ventilation scintigraphy was performed during continuous breathing of Xe-133 gas. The first breath scintigram of each patient was compared with a composite MR image composed of the sum of the individual MR images and with the individual helium-3 MR images. Ventilation defects on the two imaging modalities were compared for size, conspicuity, and concordance in presence and location. Assessment was done separately for each of four lung quadrants. RESULTS: Comparing the composite HHe MR images with Xe-133 scintigraphy, ventilation defect size, conspicuity and concordance were the same in 67% (40/60), 63% (38/60), and 62% (37/60) quadrants, respectively. Comparing the individual HHe MR image sections with the Xe-133 ventilation scan, there was concordance between the ventilation defects in 27% (16/60) of quadrants. More defects were identified on the individual HHe MR images in 62% (37/60) of quadrants. CONCLUSION: There was good agreement between composite HHe MR image and first breath Xe-133 scintigraphic images, supporting the widely held assumption that HHe MRI likely depicts first breath lung ventilation. 相似文献
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Fabia Preminger Patrice L Weiss Naomi Weintraub 《The American journal of occupational therapy》2004,58(2):193-201
PURPOSE: To determine whether there is a correlation between handwriting and keyboarding speed and accuracy, and whether handwriting and keyboarding share common underlying components. METHODS: Sixty-three typically developing 5th-grade students attended a series of 15 keyboarding lessons for a total of 5 hours. Prior to the lessons, cognitive, sensory, and motor skills related to handwriting were evaluated. Prior to and following the lessons keyboarding and handwriting accuracy and speed were also tested. Correlations were employed to examine relationships between handwriting and keyboarding skills and multiple regression analyses were used to examine the contribution of performance components to handwriting and keyboarding performance. RESULTS: Following keyboarding instruction, a significant correlation was found between handwriting and keyboarding speed, but not in accuracy of these tasks. Similarly, some of the specific tests measuring tactile and oculo-motor functions were found to be related to both handwriting and keyboarding speed, yet accuracy of these tasks did not share common underlying components. CONCLUSIONS: It appears that handwriting and keyboarding accuracy may entail different skills, suggesting that keyboarding may be a potential alternative writing tool for students with handwriting difficulties. It also appears that when students write slowly, handwriting speed should be considered prior to recommending keyboarding for these students. Additional research is required to further support these findings. 相似文献
7.
Lipoprotein glomerulopathy: first case in a white European 总被引:4,自引:0,他引:4
Meyrier A.; Dairou F.; Callard P.; Mougenot B. 《Nephrology, dialysis, transplantation》1995,10(4):546-549
Since 1988, 11 cases of a new entity, Lipoprotein glomerulopathy(LG), were described in Japan. Some of these reports suggestedthat this glomeruler lipid storage is due to excess apo E associatedwith heterozygous E2/3 apo E isoform. We report the first caseof LG in a white European with no such lipid abnormalities.Proteinuria was discovered in 1967 when he was 42. Blood pressureand renal function were normal. Family history was negative.Renal biopsy disclosed lesions which were only understood atthe time of the Japanese publications. They were composed ofendocapillary glomerular deposits. Staining for lipids disclosedcapillary loop obstruction with lipid droplets. Electron microscopyshowed confluent droplets of various sizes obstructing capillaryloops. Proteinuria progressively increased. In 1974 repeat renalbiopsy showed the same lipid deposits, now associated with focal-segmentalglomerulo-sclerosis (FSGS). Several serum lipoprotein and apolipoproteinstudies ruled out any specific lipid derangement. This suggesteda local glomerular disorder, presumably affecting the glomerularendocapillary disposal of lipids. A third biopsy showed progressiveglomerular destruction by FSGS with persistence of the lipiddroplets. Renal insufficiency progressed and haemodialysis wasstarted in 1992. This observation suggests that LG is a localglomerular, not a general lipid disorder and indicates thatthis disease is not restricted to Asian patients. 相似文献
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9.
Marc Hermier Norbert Nighoghossian Laurent Derex Patrice Adeleine Marlène Wiart Yves Berthezène Fran?ois Cotton Jean-Baptiste Pialat Pascal Dardel Jér?me Honnorat Paul Trouillas Jean-Claude Froment 《Journal of cerebral blood flow and metabolism》2003,23(11):1362-1370
Prediction of hemorrhagic transformation (HT) in patients treated by intravenous recombinant tissue-type plasminogen activator (rt-PA) is a challenging issue in acute stroke management. HT may be correlated with severe hypoperfusion. Signal changes may be observed at susceptibility-weighted magnetic resonance imaging (MRI) within large perfusion defects. A signal drop within cerebral veins at T2*-weighted gradient-echo MRI may be expected in severe ischemia, and may indicate subsequent risk of HT. The authors prospectively searched for an abnormal visibility of transcerebral veins (AVV) within the ischemic area in patients with hemispheric ischemic stroke, before they were treated with intravenous rt-PA therapy. Any correlation between AVV and baseline clinical or MRI findings, or further HT, was noted. An AVV was present in 23 of 49 patients (obvious, n = 8; moderate, n = 15), and was supported by severe hemodynamic changes at baseline MRI. The AVV was correlated with the occurrence of parenchymal hematoma type 2 at computed tomography during the first week (r = 0.44, P = 0.002). Five of six type 2 parenchymal hematomas occurred in association with obvious AVV. At multiple regression analysis, two baseline MRI factors had an independent predictive value for HT risk during the first week: the AVV and the cerebral blood volume ratio (Nagelkerke R2 = 0.48). 相似文献
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