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101.
E. Deniz Eren Wouter H. Nijhuis Freek van der Weel Aysegul Dede Eren Sana Ansari Paul H.H. Bomans Heiner Friedrich Ralph J. Sakkers Harrie Weinans Gijsbertus de With 《Microscopy research and technique》2022,85(2):469-486
Bone is a complex natural material with a complex hierarchical multiscale organization, crucial to perform its functions. Ultrastructural analysis of bone is crucial for our understanding of cell to cell communication, the healthy or pathological composition of bone tissue, and its three-dimensional (3D) organization. A variety of techniques has been used to analyze bone tissue. This article describes a combined approach of optical, scanning electron, and transmission electron microscopy for the ultrastructural analysis of bone from the nanoscale to the macroscale, as illustrated by two pathological bone tissues. By following a top-down approach to investigate the multiscale organization of pathological bones, quantitative estimates were made in terms of calcium content, nearest neighbor distances of osteocytes, canaliculi diameter, ordering, and D-spacing of the collagen fibrils, and the orientation of intrafibrillar minerals which enable us to observe the fine structural details. We identify and discuss a series of two-dimensional (2D) and 3D imaging techniques that can be used to characterize bone tissue. By doing so we demonstrate that, while 2D imaging techniques provide comparable information from pathological bone tissues, significantly different structural details are observed upon analyzing the pathological bone tissues in 3D. Finally, particular attention is paid to sample preparation for and quantitative processing of data from electron microscopic analysis. 相似文献
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Micromorphology of immature stages of Sarcophaga (Liopygia) cultellata Pandellé, 1896 (Diptera: Sarcophagidae), a forensically important fly 下载免费PDF全文
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Occurrence of fenestral diaphragms and knots in renal glomerular endothelia of diabetic mutant MafA−/−MafK+ mice as revealed in embedment‐free transmission electron microscopy 下载免费PDF全文
Kowit Chaiciwamongkol Yanyong Toomsan Tansita Arnanteerakul Hisatake Kondo Wiphawi Hipkaeo 《Microscopy research and technique》2015,78(3):207-212
Using the advantages (high contrast and transparency and efficient 3D viewing) of embedment‐free section transmission electron microscopy (TEM), the occurrence of numerous fenestral diaphragms was clearly shown in 3D en‐face viewing of the renal glomerular capillary endothelium of severe overt diabetes mellitus mice, which were generally MafA‐deficient and simultaneously MafK‐overexpressed specifically in pancreatic β‐cells. This presents another example of nephritis‐induced diaphragmed fenestrae in the renal glomerular endothelium. In addition, knot‐/umbilicus‐like structures discrete from and larger than the central knots of regular diaphragms of fenestrated endothelium were clearly demonstrated to occur randomly in the renal glomerular endothelial fenestrae of mutant mice and wild ones. The knot‐structures were revealed to be protrusions of underlining basement lamina in conventional TEM by section‐tilting observation. Microsc. Res. Tech. 78:207–212, 2015. © 2015 Wiley Periodicals, Inc. 相似文献
104.
Aged garlic extract ameliorates the oxidative stress,histomorphological, and ultrastructural changes of cisplatin‐induced nephrotoxicity in adult male rats 下载免费PDF全文
Aim: Aged garlic extract (AGE) is a natural dietary substance having different antioxidant free‐radical‐scavenger compounds that ameliorates the toxicity of the oxidative stress. This study aimed to investigate the effect of AGE on cisplatin (CP)‐induced nephrotoxicity in rats. Materials and Methods: Twenty‐four, adult male Wistar albino rats were randomly divided into four groups namely control, AGE‐treated (a single oral dose of 250 mg/kg/day for 21 days), CP‐treated (a single intraperitoneal dose of 7.5 mg/kg on Day 16), and AGE + CP‐treated (AGE at a dose of 250 mg/kg/once daily for 21 days and a single dose of CP of 7.5 mg/kg intraperitoneally on Day 16). Body weight and absolute and relative kidney weights of each rat were calculated. Serum creatinine, uric acid, and urea levels were determined. Level of malondialdehyde and reduced glutathione and activity of superoxide dismutase and catalase of renal tissues were measured. Renal specimens from each rat were prepared for both light and electron microscopic examinations. Results: Interstitial cell infiltration, hemorrhage, glomerular atrophy, necrosis, and tubular degeneration were observed after CP treatment. Superoxide dismutase and catalase activities and glutathione level were significantly decreased and malondialdehyde level was significantly increased in CP‐treated rats compared with AGE + CP‐treated animals. A remarkable improvement in the histopathological and ultrastructural changes induced by CP in renal tissues was observed in AGE + CP‐treated rats. Conclusion: AGE exhibited antioxidant effect that could ameliorate the nephrotoxic effects of CP. Microsc. Res. Tech. 78:452–461, 2015. © 2015 Wiley Periodicals, Inc. 相似文献
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Wan‐Ling Lin Xian‐Qing Yang Lai‐Hao Li Shu‐Xian Hao Jin‐Xu Wang Hui Huang Ya Wei Yan‐Yan Wu 《Journal of food science》2016,81(2):E404-E411
The research studies the ultrastructure effect on texture of crisp grass carp (CGC) and grass carp (GC) fillets inducing heating for 15, 25, and 40 min with boiling water. After heating, the hardness, fracturability, springiness, chewiness, resilience, and cohesiveness of CGC were higher than that of raw CGC, whereas the all textural characteristics of heating GC were lower obviously than that of raw GC. The hardness, fracturability, springiness, chewiness, resilience, and cohesiveness of CGC for heating 15 min were higher by 6.3%, 9.0%, 27.0%, 71.8%, 9.4%, and 23.9%, respectively, than that of raw CGC (RCGC). The hardness increasing of CGC flesh with the extension of heating time related closely to more coagulating connective tissue in interstitial spaces, especially relating to smaller muscle fiber diameter and denser muscle fiber density. The more and larger spaces between fiber and fiber with the extension of heating time results in the decrease of cohesiveness and resilience of CGC flesh. For chewiness, the stronger chewiness of cooked CGC associated with more detachment of myofiber–myocommata and fiber–fiber. Overall, the results show that the changes of texture characteristics of CGC fillet with extension of heating time correlates positively with the ultrastructure. 相似文献
107.
茄未成熟叶与衰老叶叶绿体超微结构比较研究 总被引:1,自引:0,他引:1
为揭示叶衰老对茄叶叶绿体超微结构的影响,用透射电子显微技术对茄未成熟叶和衰老叶叶肉细胞叶绿体进行比较研究.结果表明:未成熟叶叶绿体类囊体染色深,基粒柱状,许多基粒类囊体向基质中延伸,基粒之间由基质类囊体连接,基质中有大量淀粉和少量质体小球,小球体积小,直径0.1 μm以下;衰老叶叶绿体类囊体染色较浅,基粒球状,基粒类囊... 相似文献
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