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101.
Monoterpenoids (3 and 4), sesquiterpenoid (2), diterpenoid (1) and four phenethyl glucosides (5-8), together with fourteen known compounds, were isolated from the whole herb of Hyssopus cuspidatus. Their structures were determined by spectroscopic means. The abietane-type diterpenoids (1, 9, 10), rosmarinic acid (15) and salvigenin (17) inhibited leukotriene (LT) C4 secretion from primary alveolar cells of Wistar rats. 相似文献
102.
Phytochelatins (PCs) are heavy metal binding peptides that play an important role in sequestration and detoxification of heavy
metals in plants. In this study, our goal was to develop transgenic plants with increased tolerance for and accumulation of
heavy metals from soil by expressing an Arabidopsis
thaliana
AtPCS1 gene, encoding phytochelatin synthase (PCS), in Indian mustard (Brassica juncea L.). A 35S promoter fused to a FLAG–tagged AtPCS1 cDNA was expressed in Indian mustard, and transgenic lines, designated pc lines, were evaluated for tolerance to and accumulation
of Cd and Zn. Transgenic plants with moderate AtPCS1 expression levels showed significantly higher tolerance to Cd and Zn
stress, but accumulated significantly less Cd and Zn than wild type plants in both shoot and root tissues. However, transgenic
plants with highest expression of the transgene did not exhibit enhanced Cd and Zn tolerance. Shoots of Cd-treated pc plants
had significantly higher levels of phytochelatins and thiols than wild-type plants. Significantly lower concentrations of
gluthatione in Cd-treated shoot and root tissues of transgenic plants were observed. Moderate expression levels of phytochelatin
synthase improved the ability of Indian mustard to tolerate certain levels of heavy metals, but at the same time did not increase
the accumulation potential for Cd and Zn. 相似文献
103.
Noriko Miyake Hiroyasu Tsukaguchi Eriko Koshimizu Akemi Shono Satoko Matsunaga Masaaki Shiina Yasuhiro Mimura Shintaro Imamura Tomonori Hirose Koji Okudela Kandai Nozu Yuko Akioka Motoshi Hattori Norishige Yoshikawa Akiko Kitamura Hae?Il Cheong Shoji Kagami Michiaki Yamashita Atsushi Fujita Satoko Miyatake Yoshinori Tsurusaki Mitsuko Nakashima Hirotomo Saitsu Kenichi Ohashi Naoko Imamoto Akihide Ryo Kazuhiro Ogata Kazumoto Iijima Naomichi Matsumoto 《American journal of human genetics》2015,96(4):555-564
We investigated complex genomic rearrangements (CGRs) consisting of triplication copy-number variants (CNVs) that were accompanied by extended regions of copy-number-neutral absence of heterozygosity (AOH) in subjects with multiple congenital abnormalities. Molecular analyses provided observational evidence that in humans, post-zygotically generated CGRs can lead to regional uniparental disomy (UPD) due to template switches between homologs versus sister chromatids by using microhomology to prime DNA replication—a prediction of the replicative repair model, MMBIR. Our findings suggest that replication-based mechanisms might underlie the formation of diverse types of genomic alterations (CGRs and AOH) implicated in constitutional disorders. 相似文献
104.
105.
Disaccharide analysis of glycosaminoglycans synthesized by cardiac myxoma cells in tumor tissues and in cell culture 总被引:3,自引:0,他引:3
Negishi M Sakamoto H Sakamaki T Ishikawa O Kanda T Tamura J Kurabayashi M Nagai R 《Life sciences》2003,73(7):849-856
We analyzed the main disaccharide units of glycosaminoglycans synthesized by cardiac myxoma cells in vivo and in cell culture using high-performance liquid chromatography after 1-phenyl-3-methyl-5-pyrasolone labeling. Cardiac myxoma tissues contained large amounts of chondroitin-6-sulfate (46%) and hyaluronic acid (32%), along with some chondroitin-4-sulfate (13%), chondroitin (6%), and much less dermatan sulfate (3%). Cultured cardiac myxoma cells synthesized mainly chondroitin-6-sulfate. The abundant glycosaminoglycans in myxoma tissues may make up the characteristic friable gelatinous matrix which is favorable for embolism and tumor cell growth. 相似文献
106.
M Takamoto T Kaburaki A Mabuchi M Araie S Amano M Aihara A Tomidokoro A Iwase F Mabuchi K Kashiwagi S Shirato N Yasuda H Kawashima F Nakajima J Numaga Y Kawamura T Sasaki K Tokunaga 《PloS one》2012,7(7):e40107
Although intraocular pressure (IOP) is the most definitive cause of glaucoma, a subtype of open angle glaucoma (OAG) termed normal tension glaucoma (NTG), which occurs in spite of normal IOP, accounts for a large part of glaucoma cases, especially in Japan. To find common genetic variants contributing to NTG in Japanese patients, we conducted a genome-wide association study (GWAS). We performed the first screening for 531,009 autosomal SNPs with a discovery cohort of 286 cases and 557 controls, and then a second screening for the top 30 suggestive loci in an independent cohort of 183 cases and 514 controls. Our findings identified a significantly associated SNP; rs523096 [combined p-value = 7.40× 10−8, odds ratio (OR) = 2.00 with 95% confidence interval (CI) 1.55–2.58] located 10 kbp upstream of CDKN2B on chromosome 9p21. Moreover, analysis of another independent case-control set successfully replicated the results of the screening studies (combined values of all 3 stages p = 4.96 × 10−11, OR = 2.13 with 95% CI 1.69–2.68). The SNPs near rs523096 were recently reported to be associated with OAG associated with elevated IOP in primary open-angle glaucoma (POAG), the predominant subtype of glaucoma in Caucasian populations. Our results revealed that the 9p21 locus is also associated with NTG in Japanese. In addition, we identified SNPs more strongly associated with NTG. 相似文献
107.
108.
109.
Masahiro Ebihara Mitsuko Nomura Shogo Sakai Takashi Kawamura 《Inorganica chimica acta》2007,360(7):2345-2352
Reaction of tetrathiafulvalene carboxylic acid (TTFCO2H) with paddlewheel dirhodium complex Rh2(ButCO2)4 yielded TTFCO2-bridged complexes Rh2(ButCO2)3(TTFCO2) (1) and cis- and trans-Rh2(ButCO2)2(TTFCO2)2 (cis- and trans-2). Their triethylamine adducts [1(NEt3)2] and cis-[2(NEt3)2] were purified and isolated with chromatographic separation, and characterized with single crystal X-ray analysis. Trans-[2(NEt3)2] is not completely separated from a mixture of cis- and trans-[2(NEt3)2], but its single crystals were obtained from a solution of the mixture. A three-step quasi-reversible oxidation process was observed for 1 in MeCN. The first two steps correspond to the oxidation of the TTFCO2 moiety and the last one is the oxidation of the Rh2 core. The oxidation of cis-2 is observed as a two-step process with very similar E1/2 values to those of the first two processes for 1. Both 1+ and cis-22+ in MeCN at room temperature show isotropic ESR spectra with a g value of 2.008 and aH = 0.135 mT for two equivalent H atoms and aH = 0.068 mT for one H atom. The redox and ESR data of cis-2 suggest that the intramolecular interaction between the TTF moieties is very small. 相似文献
110.
Morimoto R Uehara S Yatsushiro S Juge N Hua Z Senoh S Echigo N Hayashi M Mizoguchi T Ninomiya T Udagawa N Omote H Yamamoto A Edwards RH Moriyama Y 《The EMBO journal》2006,25(18):4175-4186
Osteoclasts are involved in the catabolism of the bone matrix and eliminate the resulting degradation products through transcytosis, but the molecular mechanism and regulation of transcytosis remain poorly understood. Upon differentiation, osteoclasts express vesicular glutamate transporter 1 (VGLUT1), which is essential for vesicular storage and subsequent exocytosis of glutamate in neurons. VGLUT1 is localized in transcytotic vesicles and accumulates L-glutamate. Osteoclasts secrete L-glutamate and the bone degradation products upon stimulation with KCl or ATP in a Ca2+-dependent manner. KCl- and ATP-dependent secretion of L-glutamate was absent in osteoclasts prepared from VGLUT1-/- knockout mice. Osteoclasts express mGluR8, a class III metabotropic glutamate receptor. Its stimulation by a specific agonist inhibits secretion of L-glutamate and bone degradation products, whereas its suppression by a specific antagonist stimulates bone resorption. Finally, it was found that VGLUT1-/- mice develop osteoporosis. Thus, in bone-resorbing osteoclasts, L-glutamate and bone degradation products are secreted through transcytosis and the released L-glutamate is involved in autoregulation of transcytosis. Glutamate signaling may play an important role in the bone homeostasis. 相似文献