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121.
Nobutake Tamai Takuya Izumikawa Suguru Fukui Maiko Uemura Masaki Goto Hitoshi Matsuki Shoji Kaneshina 《生物化学与生物物理学报:生物膜》2013
Thermotropic phase behavior of diacylphosphatidylcholine (CnPC)–cholesterol binary bilayers (n = 14–16) was examined by fluorescence spectroscopy using 6-propionyl-2-(dimethylamino)naphthalene (Prodan) and differential scanning calorimetry. The former technique can detect structural changes of the bilayer in response to the changes in polarity around Prodan molecules partitioned in a relatively hydrophilic region of the bilayer, while the latter is sensitive to the conformational changes of the acyl chains. On the basis of the data from both techniques, we propose possible temperature T–cholesterol composition Xch phase diagrams for these binary bilayers. A notable feature of our phase diagrams, including our previous results for diheptadecanoylphosphatidylcholine (C17PC) and distearoylphosphatidylcholine (C18PC), is that there is a peritectic-like point around Xch = 0.15, which can be interpreted as indicating the formation of a 1:6-complex of cholesterol and CnPCs within the binary bilayer irrespective of the acyl chain length. We could give a reasonable explanation for such complex formation using the modified superlattice view. Our results also showed that the Xch value of the abolition of the main transition is almost constant for n = 14–17 (ca. 0.33), while it increases to ca. 0.50 for n = 18. By contrast, a biphasic n-dependence of Xch was observed for the abolition of the pretransition, suggesting that there are at least two antagonistic n-dependent factors. We speculate that this could be explained by the enhancement of the van der Waals interaction with increases in n and the weakening of the repulsion between the neighboring headgroups with decreases in n. 相似文献
122.
Dong Shi Tomoyo Funayama Yukihiko Mashima Yoshimasa Takano Ai Shimizu Kotaro Yamamoto MinGe Mengkegale Akiko Miyazawa Noriko Yasuda Takeo Fukuchi Haruki Abe Hidenao Ideta Kohji Nishida Toru Nakazawa Julia E. Richards Nobuo Fuse 《PloS one》2013,8(1)
Although family studies and genome-wide association studies have shown that genetic factors play a role in glaucoma, it has been difficult to identify the specific genetic variants involved. We tested 669 single nucleotide polymorphisms (SNPs) from the region of chromosome 2 that includes the GLC1B glaucoma locus for association with primary open-angle glaucoma (POAG) and normal tension glaucoma (NTG) in the Japanese population. We performed a two-stage case-control study. The first cohort consisted of 123 POAG cases, 121 NTG cases and 120 controls: the second cohort consisted of 187 POAG cases, 286 NTG cases, and 271 controls. Out of six SNPs showing significant association with POAG in the first round screening, seven SNPs were tested in the second round. Rs678350 in the HK2 gene coding sequence showed significant allelic (p = 0.0027 in Stage Two, 2.7XE-4 in meta-analysis) association with POAG, and significant allelic (p = 4.7XE-4 in Stage Two, 1.0XE-5 in meta-analysis) association with NTG. Although alleles in the TMEM182 gene did not show significant association with glaucoma in the second round, subjects with the A/A allele in TMEM182 rs869833 showed worse visual field mean deviation (p = 0.01). Even though rs2033008 in the NCK2 gene coding sequence did not show significant association in the first round, it had previously shown association with NTG so it was tested for association with NTG in round 2 (p = 0.0053 in Stage Two). Immunohistochemistry showed that both HK2 and NCK2 are expressed in the retinal ganglion cell layer. Once multi-testing was taken into account, only HK2 showed significant association with POAG and NTG in Stage Two. Our data also support previous reports of NCK2 association with NTG, and raise questions about what role TMEM182 might play in phenotypic variability. Our data suggest that HK2 may play an important role in NTG in the Japanese population. 相似文献
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Deguchi H Yasukawa K Yamasaki T Mito F Kinoshita Y Naganuma T Sato S Yamato M Ichikawa K Sakai K Utsumi H Yamada K 《Free radical biology & medicine》2011,51(9):1799-1805
Nonsteroidal anti-inflammatory drugs are the drugs of choice in the treatment of rheumatoid arthritis (RA) because of their rapid analgesic effect. However, they induce severe gastric damage in RA patients and animals by a process mediated by reactive oxygen species (ROS). Nitroxides (nitroxyl radicals) are widely used as imaging agents and antioxidants to explore the role of ROS generation in the pathogenesis of disease. In this study, the effectiveness of the newly synthesized nitroxides 8-aza-7,7,9,9-tetramethyl-1,4-dioxaspiro[4.5]undecan-8-oxyl (compound 1) and 4-oxo-2,2,6,6-tetraethylpiperidine-1-oxyl (compound 2) in the prevention of gastric ulcers in adjuvant arthritis rats treated with indomethacin was evaluated by monitoring the reaction of reactive oxygen species in gastric tissue with Overhauser-enhanced magnetic resonance imaging (OMRI). Pretreatment with all tested nitroxides suppressed the ulcers induced by indomethacin treatment in arthritic rats. OMRI using compounds 1 and 2 as well as 4-hydroxy-2,2,6,6-tetramethylpiperidine-1-oxyl (TEMPOL) demonstrated a redox imbalance in the stomach of these rats. Lipid peroxide and interleukin (IL)-1β levels in the gastric mucosa were significantly suppressed by compound 1 and TEMPOL, whereas CINC/gro, a member of the IL-8 family, was significantly suppressed by compound 1 only. These results suggest that the preventive effects of nitroxides on gastric ulcers may operate by different mechanisms. 相似文献
125.
Kawamata A Inoue A Miyajima D Hemmi H Mashima R Hayata T Ezura Y Amagasa T Yamanashi Y Noda M 《Journal of cellular physiology》2011,226(12):3087-3093
Osteoporosis causes fractures that lead to reduction in the quality of life and it is one of the most prevalent diseases as it affects approximately 10% of the population. One of the important features of osteoporosis is osteopenia. However, its etiology is not fully elucidated. Dok-1 and Dok-2 are adaptor proteins acting downstream of protein tyrosine kinases that are mainly expressed in the cells of hematopoietic lineage. Although these proteins negatively regulate immune system, their roles in bone metabolism are not understood. Here, we analyzed the effects of Dok-1 and Dok-2 double-deficiency on bone. Dok-1/2 deficiency reduced the levels of trabecular and cortical bone mass compared to wildtype. In addition, Dok-1/2 deficiency increased periosteal perimeters and endosteal perimeters of the mid shaft of long bones. Histomorphometric analysis of the bone parameters indicated that Dok-1/2 deficiency did not significantly alter the levels of bone formation parameters including mineralizing surface/bone surface (MS/BS), mineral apposition rate (MAR) and bone formation rate (BFR). In contrast, Dok-1/2 deficiency enhanced the levels of bone resorption parameters including osteoclast number (N.Oc/BS) and osteoclast surface (Oc.S/BS). Analyses of individual osteoclastic activity indicated that Dok-1/2 deficiency enhanced pit formation. Systemically, Dok-1/2 deficiency increased the levels of urinary deoxypyridinoline (Dpyr). Search for the target point of the Dok-1/2 deficiency effects on osteoclasts identified that the mutation enhanced sensitivity of osteoclast precursors to macrophage colony-stimulating factor. These data revealed that Dok-1 and Dok-2 deficiency induces osteopenia by activation of osteoclasts. 相似文献
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128.
Mesenchymal progenitor cells in adult human dental pulp and their ability to form bone when transplanted into immunocompromised mice 总被引:3,自引:0,他引:3
Otaki S Ueshima S Shiraishi K Sugiyama K Hamada S Yorimoto M Matsuo O 《Cell biology international》2007,31(10):1191-1197
The technique of tissue engineering is developing for the restoration of lost tissues. This new technique requires cells that fabricate tissue. Mesenchymal stem cells in bone marrow have been used as the cell source for this technique; however, dental pulp cells have recently been shown to possess stem-cell-like properties. We earlier demonstrated that dental pulp cells proliferate and produce an extracellular matrix that subsequently becomes mineralized in vitro. We now report that such dental pulp cells (first to eighth passage) produced bone instead of dentin when those cells were implanted into subcutaneous sites in immunocompromised mice with HA/TCP powder as their carrier. This evidence shows that dental pulp cells are the common progenitors of odontoblasts and osteoblasts, or dental pulp cells are mesenchymal stem cells themselves. It is expected that dental pulp cells can be a useful candidate cell source for tissue engineering, and contain the potential of new therapeutic approaches for the restoration of damaged or diseased tissue. 相似文献
129.
Nakajima Suguru Suzuki Masahiro Kaneko Yoshiyuki Kobayashi Masato Igarashi Takahiro Gon Yasuhiro Yoshino Atsuo Uchiyama Makoto 《Sleep and biological rhythms》2019,17(4):459-461
Sleep and Biological Rhythms - We report an adolescent case of malignant brain tumor who presented with an irregular sleep–wake cycle as the first significant clinical symptom. The patient... 相似文献
130.