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Plant Ecology - Japanese stinging nettles, Urtica thunbergiana, in Nara Park (660 ha), central Japan, where several hundred sika deer Cervus nippon have been protected for... 相似文献
84.
Ichikawa H No H Takei S Takashimizu I Yue F Cui L Ogiwara N Johkura K Nishimoto Y Sasaki K 《Cryobiology》2007,54(3):290-293
Cryopreservation of embryonic stem (ES) cells is essential to establish them as a resource for regenerative therapy. We evaluated survival adhesion rate, cell structure, gene expression, and multipotency of frozen and thawed embryoid bodies (EBs) derived from mouse ES cells. EBs were cryopreserved using the BICELL and the Program Freezer. After one week the EBs were thawed and cultured. EBs prepared in the Program Freezer had the highest survival adhesion (Program Freezer; 55-69%, BICELL; 30-38%). Though many cells in the thawed EBs were damaged, some were not, especially those prepared in the Program Freezer. RT-PCR analysis showed that genes characteristic of the three embryonic germ layers were expressed in thawed EBs cultured for one week. EBs transplanted into mice formed teratomas consisting of cells derived from the three germ layers. In conclusion, EBs frozen in the Program Freezer had higher survival adhesion rates compared to the BICELL and formed differentiated cells characteristic of the three embryonic germ layers. 相似文献
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Background
Selective serotonin-reuptake inhibitors (SSRIs) are commonly prescribed for the treatment of depression and can be used as nonhormonal alternatives to manage hot flashes for women with a history of breast cancer and unable to take hormone replacement therapy. There are, however, few reports on the efficacy of SSRIs for the treatment of natural postmenopausal climacteric symptoms. In this pilot study, we evaluate the SSRI, fluvoxamine, for controlling climacteric symptoms and vasomotor symptoms, in particular. 相似文献87.
Yamato M Shiba T Yoshida M Ide T Seri N Kudou W Kinugawa S Tsutsui H 《The FEBS journal》2007,274(15):3855-3863
Plasma concentrations of free fatty acids are increased in metabolic syndrome, and the increased fatty acids may cause cellular damage via the induction of oxidative stress. The present study was designed to determine whether the increase in fatty acids can modify the free sulfhydryl group in position 34 of albumin (Cys34) and enhance the redox-cycling activity of the copper-albumin complex in high-fat diet-induced obese mice. The mice were fed with commercial normal diet or high-fat diet and water ad libitum for 3 months. The high-fat diet-fed mice developed obesity, hyperlipemia, and hyperglycemia. The plasma fatty acid/albumin ratio also significantly increased in high-fat diet-fed mice. The increased fatty acid/albumin ratio was associated with conformational changes in albumin and the oxidation of sulfhydryl groups. Moreover, an ascorbic acid radical, an index of redox-cycling activity of the copper-albumin complex, was detected only in the plasma from obese mice, whereas the plasma concentrations of ascorbic acid were not altered. Plasma thiobarbituric acid reactive substances were significantly increased in the high-fat diet group. These results indicate that the increased plasma fatty acids in the high-fat diet group resulted in the activated redox cycling of the copper-albumin complex and excessive lipid peroxidation. 相似文献
88.
Bioactive N-acylethanolamines, including the endocannabinoid anandamide and anti-inflammatory N-palmitoylethanolamine, are hydrolyzed to fatty acids and ethanolamine in animal tissues by the catalysis of fatty acid amide hydrolase (FAAH). We recently cloned cDNA of N-acylethanolamine-hydrolyzing acid amidase (NAAA), another enzyme catalyzing the same reaction, from human, rat, and mouse. NAAA reveals no sequence homology with FAAH and belongs to the choloylglycine hydrolase family. The most striking catalytic property of NAAA is pH optimum at 4.5-5, which is consistent with its immunocytochemical localization in lysosomes. In rat, NAAA is highly expressed in lung, spleen, thymus, and intestine. Notably, the expression level of NAAA is exceptionally high in rat alveolar macrophages. The primary structure of NAAA exhibits 33-35% amino acid identity to that of acid ceramidase, a lysosomal enzyme hydrolyzing ceramide to fatty acid and sphingosine. NAAA actually showed a low, but detectable ceramide-hydrolyzing activity, while acid ceramidase hydrolyzed N-lauroylethanolamine. Thus, NAAA is a novel lysosomal hydrolase, which is structurally and functionally similar to acid ceramidase. These results suggest a unique role of NAAA in the degradation of N-acylethanolamines. 相似文献
89.
Goki Tanaka Tomoyuki Yamanaka Yoshiaki Furukawa Naoko Kajimura Kaoru Mitsuoka Nobuyuki Nukina 《生物化学与生物物理学报:疾病的分子基础》2019,1865(6):1410-1420
Synucleinopathies comprise a diverse group of neurodegenerative diseases including Parkinson's disease (PD), dementia with Lewy bodies, and multiple system atrophy. These share a common pathological feature, the deposition of alpha-synuclein (a-syn) in neurons or oligodendroglia. A-syn is highly conserved in vertebrates, but the primary sequence of mouse a-syn differs from that of human at seven positions. However, structural differences of their aggregates remain to be fully characterized. In this study, we found that human and mouse a-syn aggregated in vitro formed morphologically distinct amyloid fibrils exhibiting twisted and straight structures, respectively. Furthermore, we identified different protease-resistant core regions, long and short, in human and mouse a-syn aggregates. Interestingly, among the seven unconserved amino acids, only A53T substitution, one of the familial PD mutations, was responsible for structural conversion to the straight-type. Finally, we checked whether the structural differences are transmissible by seeding and found that human a-syn seeded with A53T aggregates formed straight-type fibrils with short protease-resistant cores. These results suggest that a-syn aggregates form sequence-dependent polymorphic fibrils upon spontaneous aggregation but become seed structure-dependent upon seeding. 相似文献
90.
Xiaoxu Cui Chengyu Hao Lijing Gong Naoko Kajitani Stefan Schwartz 《Nucleic acids research》2022,50(5):2782
Human papillomavirus type 16 (HPV16) E1 and E6 proteins are produced from mRNAs with retained introns, but it has been unclear how these mRNAs are generated. Here, we report that hnRNP D act as a splicing inhibitor of HPV16 E1/E2- and E6/E7-mRNAs thereby generating intron-containing E1- and E6-mRNAs, respectively. N- and C-termini of hnRNP D contributed to HPV16 mRNA splicing control differently. HnRNP D interacted with the components of splicing machinery and with HPV16 RNA to exert its inhibitory function. As a result, the cytoplasmic levels of intron-retained HPV16 mRNAs were increased in the presence of hnRNP D. Association of hnRNP D with HPV16 mRNAs in the cytoplasm was observed, and this may correlate with unexpected inhibition of HPV16 E1- and E6-mRNA translation. Notably, hnRNP D40 interacted with HPV16 mRNAs in an HPV16-driven tonsillar cancer cell line and in HPV16-immortalized human keratinocytes. Furthermore, knockdown of hnRNP D in HPV16-driven cervical cancer cells enhanced production of the HPV16 E7 oncoprotein. Our results suggest that hnRNP D plays significant roles in the regulation of HPV gene expression and HPV-associated cancer development. 相似文献