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991.
Kosuge H Sherlock SP Kitagawa T Terashima M Barral JK Nishimura DG Dai H McConnell MV 《PloS one》2011,6(1):e14523
Background
FeCo/graphitic-carbon nanocrystals (FeCo/GC) are biocompatible, high-relaxivity, multi-functional nanoparticles. Macrophages represent important cellular imaging targets for assessing vascular inflammation. We evaluated FeCo/GC for vascular macrophage uptake and imaging in vivo using fluorescence and MRI.Methods and Results
Hyperlipidemic and diabetic mice underwent carotid ligation to produce a macrophage-rich vascular lesion. In situ and ex vivo fluorescence imaging were performed at 48 hours after intravenous injection of FeCo/GC conjugated to Cy5.5 (n = 8, 8 nmol of Cy5.5/mouse). Significant fluorescence signal from FeCo/GC-Cy5.5 was present in the ligated left carotid arteries, but not in the control (non-ligated) right carotid arteries or sham-operated carotid arteries (p = 0.03 for ligated vs. non-ligated). Serial in vivo 3T MRI was performed at 48 and 72 hours after intravenous FeCo/GC (n = 6, 270 µg Fe/mouse). Significant T2* signal loss from FeCo/GC was seen in ligated left carotid arteries, not in non-ligated controls (p = 0.03). Immunofluorescence staining showed colocalization of FeCo/GC and macrophages in ligated carotid arteries.Conclusions
FeCo/GC accumulates in vascular macrophages in vivo, allowing fluorescence and MR imaging. This multi-functional high-relaxivity nanoparticle platform provides a promising approach for cellular imaging of vascular inflammation. 相似文献992.
This study aims to clarify age-related changes of body composition structure in terms of the percentages of body fat and muscle (muscle mass/weight×100) in preschool children by using BMI. The subjects were 533 preschool children, comprising 260 boys and 273 girls. Regression analysis for BMI was performed and a regression polynomial of a proper order was determined. After examining the validity of the order in a regression polynomial for %Fat and muscle percentages for BMI, a regression polynomial evaluation chart was made up. After judging the degree of fat or muscle accumulation from BMI and the fat or muscle percentages for each age group of the boys and girls, a frequency distribution map of excessive development and underdevelopment of fat and muscle was drawn up and its age-related changes were examined. As a result, a complementary relationship was confirmed to exist between BMI and %Fat in preschool children. In contrast, an opposite relationship was found for BMI and muscle percentages. These results suggest that BMI can be used as an index of muscle percentages as well as %Fat. As a final result, the distribution composition map of fat and muscle percentages for BMI does not show changes with age from infancy in preschool boys as a whole, but it does show such changes in girls. It is inferred that preschool girls show, due to early maturity, earlier changes (fat decrease) toward an integrated child's body than do boys. 相似文献
993.
Isolation and in vitro expansion of human colonic stem cells 总被引:1,自引:0,他引:1
Jung P Sato T Merlos-Suárez A Barriga FM Iglesias M Rossell D Auer H Gallardo M Blasco MA Sancho E Clevers H Batlle E 《Nature medicine》2011,17(10):1225-1227
Here we describe the isolation of stem cells of the human colonic epithelium. Differential cell surface abundance of ephrin type-B receptor 2 (EPHB2) allows the purification of different cell types from human colon mucosa biopsies. The highest EPHB2 surface levels correspond to epithelial colonic cells with the longest telomeres and elevated expression of intestinal stem cell (ISC) marker genes. Moreover, using culturing conditions that recreate the ISC niche, a substantial proportion of EPHB2-high cells can be expanded in vitro as an undifferentiated and multipotent population. 相似文献
994.
995.
Sato A Nagasaka S Furihata K Nagata S Arai I Saruwatari K Kogure T Sakuda S Nagasawa H 《Nature chemical biology》2011,7(4):197-199
It has been thought that phosphorus in biominerals made of amorphous calcium carbonate (ACC) might be related to ACC formation, but no such phosphorus-containing compounds have ever been identified. Crustaceans use ACC biominerals in exoskeleton and gastroliths so that they will have easy access to calcium carbonate inside the body before and after molting. We have identified phosphoenolpyruvate and 3-phosphoglycerate, intermediates of the glycolytic pathway, in exoskeleton and gastroliths and found them important for stabilizing ACC. 相似文献
996.
GW182 family proteins play important roles in microRNA (miRNA)-mediated gene silencing. They interact with Argonaute (Ago) proteins and localize in processing bodies, which are cytoplasmic foci involved in mRNA degradation and storage. Here, we demonstrated that human GW182 paralog, TNRC6A, is a nuclear–cytoplasmic shuttling protein, and its subcellular localization is conducted by a nuclear export signal (NES) and a nuclear localization signal (NLS) identified in this study. TNRC6A with mutations in its NES region was predominantly localized in the nucleus in an Ago-independent manner. However, it was found that TNRC6A could bring Ago protein into the nucleus via its Ago-interacting motif(s). Furthermore, miRNAs were also colocalized with nuclear TNRC6A-Ago and exhibited gene silencing activity. These results proposed the possibility that TNRC6A plays an important role in navigating Ago protein into the nucleus to lead miRNA-mediated gene silencing. 相似文献
997.
Atsushi Hayashi Toshiro Sato Nobuhiko Kamada Yohei Mikami Katsuyoshi Matsuoka Tadakazu Hisamatsu Toshifumi Hibi Axel Roers Hideo Yagita Toshiaki Ohteki Akihiko Yoshimura Takanori Kanai 《Cell host & microbe》2013,13(6):711-722
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998.
999.
Yuichiro Maruyama Koji Okuda Toshiro Ogata Masafumi Yasunaga Hiroto Ishikawa Yusuke Hirakawa Kenjiro Fukuyo Hiroyuki Horiuchi Osamu Nakashima Hisafumi Kinoshita 《PloS one》2013,8(10)
Background
Cystic lesions of the liver consist of a heterogeneous group of disorders that can present diagnostic and therapeutic challenges.Methods
A retrospective review of all medical records of adult patients diagnosed with large (>7 cm) cystic lesions of the liver between January 2000 and December 2011, at Kurume University Hospital. Cases with polycystic disease were excluded.Results
Twenty three patients were identified. The mean size was 13.9 cm (range, 7-22cm). The majority of simple cysts were found in women (females: males, 2: 21). In 19 patients, the cyst was removed surgically by wide deroofing (laparoscopically in 16 cases, combined with ethanol sclerotherapy in 13 cases). Infection of the liver cyst occurred in one patient, who later underwent central bi-segmentectomy.Conclusion
Simple large cysts of the liver can be successfully treated by laparoscopic deroofing and alcohol sclerotherapy. Large hepatic cyst considered to need drainage should be removed surgically to avoid possible infection. 相似文献1000.
Makoto Taniguchi Toshiro Okazaki 《Biochimica et Biophysica Acta (BBA)/Molecular and Cell Biology of Lipids》2014,1841(5):692-703
Sphingomyelin constitutes membrane microdomains such as lipid raft, caveolae, and clathrin-coated pits and implicates in the regulation of trans-membrane signaling. On the other hand, sphingomyelin emerges as an important molecule to generate bioactive sphingolipids through ceramide. Sphingomyelin synthase is an enzyme that generates sphingomyelin and diacylglycerol from phosphatidylcholine and ceramide. Although ceramide has a well-known role as a lipid mediator to regulate cell death and survival, the only known biological role of sphingomyelin regulated by sphingomyelin synthases was limited to being a source of bioactive lipids. Here, we describe the basic characters of sphingomyelin synthases and discuss additional roles for sphingomyelin and sphingomyelin synthase in biological functions including cell migration, apoptosis, autophagy, and cell survival/proliferation as well as in human disorders such as cancer and cardiovascular disorders. It is expected that a better understanding of the role of sphingomyelin regulated by sphingomyelin synthase will shed light on new mechanisms in cell biology, physiology and pathology. In the future, novel therapeutic procedures for currently incurable diseases could be developed through modifying the function of not only sphingolipids, such as sphingomyelin and ceramide, but also of their regulatory enzymes. This article is part of a Special Issue entitled New Frontiers in Sphingolipid Biology. 相似文献