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991.
Ken-Go Hayashi Koichi Ushizawa Misa Hosoe Toru Takahashi 《Reproductive biology and endocrinology : RB&E》2010,8(1):11
Background
Bovine follicular development is regulated by numerous molecular mechanisms and biological pathways. In this study, we tried to identify differentially expressed genes between largest (F1) and second-largest follicles (F2), and classify them by global gene expression profiling using a combination of microarray and quantitative real-time PCR (QPCR) analysis. The follicular status of F1 and F2 were further evaluated in terms of healthy and atretic conditions by investigating mRNA localization of identified genes. 相似文献992.
993.
Richard Cornette Yasushi Kanamori Masahiko Watanabe Yuichi Nakahara Oleg Gusev Kanako Mitsumasu Keiko Kadono-Okuda Michihiko Shimomura Kazuei Mita Takahiro Kikawada Takashi Okuda 《The Journal of biological chemistry》2010,285(46):35889-35899
Some organisms are able to survive the loss of almost all their body water content, entering a latent state known as anhydrobiosis. The sleeping chironomid (Polypedilum vanderplanki) lives in the semi-arid regions of Africa, and its larvae can survive desiccation in an anhydrobiotic form during the dry season. To unveil the molecular mechanisms of this resistance to desiccation, an anhydrobiosis-related Expressed Sequence Tag (EST) database was obtained from the sequences of three cDNA libraries constructed from P. vanderplanki larvae after 0, 12, and 36 h of desiccation. The database contained 15,056 ESTs distributed into 4,807 UniGene clusters. ESTs were classified according to gene ontology categories, and putative expression patterns were deduced for all clusters on the basis of the number of clones in each library; expression patterns were confirmed by real-time PCR for selected genes. Among up-regulated genes, antioxidants, late embryogenesis abundant (LEA) proteins, and heat shock proteins (Hsps) were identified as important groups for anhydrobiosis. Genes related to trehalose metabolism and various transporters were also strongly induced by desiccation. Those results suggest that the oxidative stress response plays a central role in successful anhydrobiosis. Similarly, protein denaturation and aggregation may be prevented by marked up-regulation of Hsps and the anhydrobiosis-specific LEA proteins. A third major feature is the predicted increase in trehalose synthesis and in the expression of various transporter proteins allowing the distribution of trehalose and other solutes to all tissues. 相似文献
994.
Yosuke Demizu Nanako Yamagata Yukiko Sato Mitsunobu Doi Masakazu Tanaka Haruhiro Okuda Masaaki Kurihara 《Journal of peptide science》2010,16(3):153-158
One chiral L ‐valine (L ‐Val) was inserted into the C‐terminal position of achiral peptide segments constructed from α‐aminoisobutyric acid (Aib) and α,β‐dehydrophenylalanine (ΔZPhe) residues. The IR, 1H NMR and CD spectra indicated that the dominant conformations of the pentapeptide Boc‐Aib‐ΔPhe‐(Aib)2‐L ‐Val‐NH‐Bn (3) and the hexapeptide Boc‐Aib‐ΔPhe‐(Aib)3‐L ‐Val‐NH‐Bn (4) in solution were both right‐handed (P) 310‐helical structures. X‐ray crystallographic analyses of 3 and 4 revealed that only a right‐handed (P) 310‐helical structure was present in their crystalline states. The conformation of 4 was also studied by molecular‐mechanics calculations. Copyright © 2010 European Peptide Society and John Wiley & Sons, Ltd. 相似文献
995.
Yosuke Demizu Masakazu Tanaka Mitsunobu Doi Masaaki Kurihara Haruhiro Okuda Hiroshi Suemune 《Journal of peptide science》2010,16(11):621-626
A single chiral cyclic α,α‐disubstituted amino acid, (3S,4S)‐1‐amino‐(3,4‐dimethoxy)cyclopentanecarboxylic acid [(S,S)‐Ac5cdOM], was placed at the N‐terminal or C‐terminal positions of achiral α‐aminoisobutyric acid (Aib) peptide segments. The IR and 1H NMR spectra indicated that the dominant conformations of two peptides Cbz‐[(S,S)‐Ac5cdOM]‐(Aib)4‐OEt ( 1) and Cbz‐(Aib)4‐[(S,S)‐Ac5cdOM]‐OMe (2) in solution were helical structures. X‐ray crystallographic analysis of 1 and 2 revealed that a left‐handed (M) 310‐helical structure was present in 1 and that a right‐handed (P) 310‐helical structure was present in 2 in their crystalline states. Copyright © 2010 European Peptide Society and John Wiley & Sons, Ltd. 相似文献
996.
Tomoyuki Terada Kei‐ichi Okamoto Jun‐ichi Nishikawa Takeshi Miura Toru Nishinaka Tsutomu Nishihara 《Journal of biochemical and molecular toxicology》2010,24(1):60-65
A cDNA of rat liver thioltransferase was cloned and then expressed using pMAL‐c expression vector in Escherichia coli. Recombinant rat liver thioltransferase was expressed as a fusion protein with maltose‐binding protein and then purified by amylose resin column chromatography to be homogeneity on 12.5% SDS‐polyacrylamide gel electrophoretic analysis. The expressed proteins were shown as two bands at around 53 and 41 kDa, suggesting that the high molecular one was a fusion protein of recombinant thioltransferase (11.7 plus 41 kDa) and the other (smaller one) was a maltose‐binding protein (41 kDa). A recombinant thioltransferase catalyzed a thiol/disulfide exchange reaction in the same way as thioltransferases purified from various sources. Compared with wild type, the mutants C23A, C26A, C79A, and C83A showed 0%, 17%, 82%, and 86% in the enzymatic activity, respectively. In addition, wild‐type‐transfected bacteria expressed in bacterial cells showed a strong resistance to H2O2 treatment as well as the case of active mutants (C79A and C83A), but inactive mutants (C23A and C26A) showed no resistance to H2O2 treatment as same as mocktransfection. Thioltransferase can be important for survival of bacterial cells under oxidative stress. © 2010 Wiley Periodicals, Inc. J Biochem Mol Toxicol 24:60–65, 2010; Published online in Wiley InterScience ( www.interscience.wiley.com ). DOI 10.1002/jbt.20312 相似文献
997.
998.
We analyse, from a mathematical point of view, the global stability of equilibria for models describing the interaction between infectious agents and humoral immunity. We consider the models that contain the variables of pathogens explicitly. The first model considers the situation where only a single strain exists. For the single strain model, the disease steady state is globally asymptotically stable if the basic reproductive ratio is greater than one. The other models consider the situations where multiple strains exist. For the multi-strain models, the disease steady state is globally asymptotically stable. In the model that does not explicitly contain an immune variable, only one strain with the maximum basic reproductive ratio can survive at the steady state. However, in our models explicitly involving the immune system, multiple strains coexist at the steady state. 相似文献
999.
Tamada K Tomonaga S Hatanaka F Nakai N Takao K Miyakawa T Nakatani J Takumi T 《PloS one》2010,5(12):e15126
Autism spectrum disorders (ASDs) have garnered significant attention as an important grouping of developmental brain disorders. Recent genomic studies have revealed that inherited or de novo copy number variations (CNVs) are significantly involved in the pathophysiology of ASDs. In a previous report from our laboratory, we generated mice with CNVs as a model of ASDs, with a duplicated mouse chromosome 7C that is orthologous to human chromosome 15q11-13. Behavioral analyses revealed paternally duplicated (patDp/+) mice displayed abnormal behaviors resembling the symptoms of ASDs. In the present study, we extended these findings by performing various behavioral tests with C57BL/6J patDp/+ mice, and comprehensively measuring brain monoamine levels with ex vivo high performance liquid chromatography. Compared with wild-type controls, patDp/+ mice exhibited decreased locomotor and exploratory activities in the open field test, Y-maze test, and fear-conditioning test. Furthermore, their decreased activity levels overcame increased appetite induced by 24 hours of food deprivation in the novelty suppressed feeding test. Serotonin levels in several brain regions of adult patDp/+ mice were lower than those of wild-type control, with no concurrent changes in brain levels of dopamine or norepinephrine. Moreover, analysis of monoamines in postnatal developmental stages demonstrated reduced brain levels of serotonin in young patDp/+ mice. These findings suggest that a disrupted brain serotonergic system, especially during postnatal development, may generate the phenotypes of patDp/+ mice. 相似文献
1000.
Yosuke Kita Atsuko Gunji Kotoe Sakihara Masumi Inagaki Makiko Kaga Eiji Nakagawa Toru Hosokawa 《PloS one》2010,5(6)