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81.
The once accepted idea that LEF-1 transports beta-catenin into nuclei has recently been challenged by experiments using exogenous beta-catenin. Here, we investigated the effects of beta-catenin and LEF-1 on nuclear import of beta-catenin using different combinations of exogenous and endogenous molecules over longer lengths of time than previously studied. Nuclear beta-catenin is not detectable in corneal fibroblasts and epithelia or NIH 3T3 and MDCK cells. In LEF-1 transfections, we show that the B-box of LEF-1 is required to move cytoplasmic endogenous beta-catenin into the nuclei of such cells, proving that LEF-1 does transport endogenous beta-catenin into nuclei. Moreover, transfection of uveal melanoma cells with B-box deficient LEF-1 inhibits nuclear import of beta-catenin by endogenous LEF-1. However, the movement of overexpressed exogenous beta-catenin into nuclei is unaffected by the presence or absence of LEF-1 and forms abnormal nuclear aggregates that are a prelude to subsequent apoptosis. We conclude that nuclear transport of exogenous beta-catenin independently of LEF-1 has questionable physiological significance. 相似文献
82.
摘要 目的:本研究旨在探讨对比分析IPS e.max Press铸瓷高嵌体与普兰梅卡CADCAM系统制作的高嵌体修复后牙牙体缺损的效果。方法:以2021年8月-2022年8月我院诊治的60例(86颗)后牙牙体缺损患者为研究对象,采用随机数字表法将其分为研究组(给予普兰梅卡CADCAM系统制作的高嵌体修复)和对照组(给予IPS e.max Press铸瓷高嵌体修复)各30例,对比两组修复前及修复1年后咀嚼功能、牙龈情况、RANK、CXCL16水平、IL-6、IL-8水平,统计修复结果及美牙效果满意度。结果:(1)修复前,两组咀嚼功能比较无差异(P>0.05);修复1年后,研究组咀嚼功能优于对照组(P<0.05);(2)修复前,两组牙龈指数、菌斑指数评分比较无差异(P>0.05);修复1年后,研究组牙龈指数、菌斑指数评分优于对照组(P<0.05);(3)修复前,两组RANK、CXCL16水平比较无差异(P>0.05);修复1年后,研究组RANK、CXCL16水平低于对照组(P<0.05);(4)修复前,两组IL-6、IL-8水平比较无差异(P>0.05);修复1年后,研究组IL-6、IL-8水平与对照组比较(P>0.05);(5)修复1年后,研究组修复体边缘适合性、修复体邻面解剖形态优于对照组(P<0.05);两组修复体表面及边缘着色、修复体折裂与固位比较,差异不显著(P>0.05);(6)修复1年后,研究组美牙效果满意度优于对照组(P<0.05)。结论:与IPS e.max Press铸瓷高嵌体相比,普兰梅卡CADCAM系统制作的高嵌体修复后牙牙体缺损的效果更佳,能够提高咀嚼功能,改善牙龈指数,提高美牙效果满意度。 相似文献
83.
Anne Fleury Michel Lemullois Grard Coffe 《Biology of the cell / under the auspices of the European Cell Biology Organization》1998,90(4):307-318
Ciliates assemble basal bodies in great number at many stages of the life-cycle. In order to understand their assembly mechanisms, we screened a library of monoclonal antibodies directed against pericentriolar material. One of these antibodies, CTR210, was used previously to follow steps of this assembly process: in Paraurostyla, new basal bodies appear along a scaffold of linear structures recognized by this antibody. The very unusual behavior of this antigen deserved confirmation in other species. In the present study, we show by immunofluorescence that, in another phylogenetically very distant species, Euplotes, basal bodies are assembled in the same pathway during division. In addition, this antibody recognizes a filamentous ring located at the division furrow and linking many basal body assemblages. By cell fractionation and cytoskeletal extraction, we obtained fractions enriched in basal bodies and associated material. Such fractions still display a high complexity in protein composition. These fractions were used to characterize the main target of the antibody as a doublet of 45 kDa. These results confirm previous results in terms of functionality of the protein recognized by the antibody, but raise new questions in terms of the assignment of the recognized protein to the HSP70 family as hypothesized previously. 相似文献
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Jody L. Clasey Claude Bouchard Laurie Wideman Jill Kanaley C. David Teates Michael O. Thorner Mark L. Hartman Arthur Weltman 《Obesity (Silver Spring, Md.)》1997,5(5):395-401
CLASEY, JODY L, CLAUDE BOUCHARD, LAURIE WIDEMAN, JILL KANALEY, C DAVID TEATES, MICHAEL O THORNER, MARK L HARTMAN, ARTHUR WELTMAN. The influence of anatomical boundaries, age, and sex on the assessment of abdominal visceral fat. Single-slice abdominal computed tomography (CT) scanning has been used extensively for the measurement of abdominal visceral fat (AYF). Optimal anatomical scan location and pixel density ranges have been proposed and are specifically reported to allow for the replication and standardization of AVF measurements. Standardization of the anatomical boundaries for CT measurement of AVF and the influence of age and gender on results obtained with different boundary locations have received much less attention. To determine the influence of three boundary analysis methods (AVF-1, AVF-2, and AVF-3) on the measurement of AVF by CT, 54 older (60 years to 79 years) and 37 younger (20 years to 29 years) healthy men and women were examined. The measurement boundary for AVF-1 was the internal most aspect of the abdominal and oblique muscle walls, and the posterior aspect of the vertebral body. AVF-2 used fat measurements enclosed in a boundary formed by the midpoint of the abdominal and oblique muscle walls, and the most posterior aspect of the spinous process. AVF-3 used fat measurements enclosed in a boundary formed by the external border of the abdominal and oblique muscle walls, and the external border of the erector spinae. Greater AVF measures were obtained with AVF-2 and AVF-3 compared with AVF-1 (p<0.0001). These differences were greater in older compared with younger subjects (p<0.0001) and greater in women compared with men (p<0.02). The significantly greater AVF measurements obtained with AVF-2 and AVF-3 resulted from the inclusion of larger amounts of fat that are not drained by the portal circulation. This included retroperitoneal, intermuscular, and intramuscular lipid droplets, which increase with aging. On the basis of these results, we recommend the AVF-1 anatomical boundaries for the measurement of AVF in clinical investigations, particularly with older subjects. These data demonstrate the importance of precise and reproducible anatomical boundaries for the measurement of AVF, particularly in longitudinal studies. 相似文献
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88.
Malory Randon Christophe Bonenfant Jacques Michallet Thierry Chevrier Carole Toïgo Jean-Michel Gaillard Marion Valeix 《Population Ecology》2020,62(2):244-257
In a context of changing carnivore populations worldwide, it is crucial to understand the consequences of these changes for prey populations. The recolonization by wolves of the French Vercors mountain range and the long-term monitoring (2001–2017) of roe deer in this area provided a unique opportunity to assess the effects of wolves on this prey. Roe deer was the main prey of wolves in the west Vercors mountain range during this recolonization. We compared roe deer abundance and fawn body mass in two contrasted areas of a wolf pack territory: a central area (core of the territory characterized by an intense use by wolves) and a peripheral area (used more occasionally). Roe deer population growth rates were lower in the central area between 2001 and 2006, resulting in a decline in roe deer abundance. Roe deer abundance substantially dropped in the two study areas after an extremely severe winter but the abundance of roe deer in the central area facing with wolves was slower to recover and remained at lower abundance levels for 6 years. Fawn body mass was consistently lower in the central area, varied similarly as roe deer abundance, and was not influenced by weather conditions or red deer population abundance. Altogether, the effects of wolves on roe deer in the central area occurred during a 10-year period following the establishment of wolves, through the interplay between wolf predation (before wolves started preying on red deer), harsh winter conditions and possibly naivety of prey to this recolonizing predator. 相似文献
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90.
《Reports of Practical Oncology and Radiotherapy》2020,25(4):684-691
PurposeRestricted studies comparing different dose rate parameters are available while ITV-based VMAT lung SBRT planning leads to perform the analysis of the most suitable parameters of the external beams used. The special emphasis was placed on the impact of dose rate on dose distribution variations in target volumes due to interplay effects.MethodsFour VMAT plans were calculated for 15 lung tumours using 6 MV photon beam quality (flattening filter FF vs. flattening filter free FFF beams) and maximum dose rate of 600 MU/min, 1000 MU/min and 1400 MU/min. Three kinds of motion simulations were performed finally giving 180 plans with perturbed dose distributions.Results6FFF-1400 MUs/min plans were characterized by the shortest beam on time (1.8 ± 0.2 min). Analysing the performed motion simulation results, the mean dose (Dmean) is not a sensitive parameter to related interplay effects. Looking for local maximum and local minimum doses, some discrepancies were found, but their significance was presented for individual patients, not for the whole cohort. The same was observed for other verified dose metrics.ConclusionsGenerally, the evaluation of VMAT robustness between FF and FFF concepts against interplay effect showed a negligible effect of simulated motion influence on tumour coverage among different photon beam quality parameters. Due to the lack of FFF beams, smaller radiotherapy centres are able to perform ITV-based VMAT lung SBRT treatment in a safe way. Radiotherapy department having FFF beams could perform safe, fast and efficient ITV-based VMAT lung SBRT without a concern about significance of interplay effects. 相似文献