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991.
Ohyama Akio Yamaguchi Hirotaka Miyatake Koji Negoro Satomi Nunome Tsukasa Saito Takeo Fukuoka Hiroyuki 《Molecular biology reports》2022,49(10):9147-9157
Molecular Biology Reports - The appearance quality of the eggplant (Solanum melongena L.) fruit is an important trait that influences its commercial value. It is known that quality traits such as... 相似文献
992.
Lawrence K. F. Wong Zhiwei Luo Nobuyuki Kurusu Keiji Fujino 《Computer methods in biomechanics and biomedical engineering》2019,22(8):806-814
A computer simulation model was developed to study the dynamic behavior of the cervical spine during cervical traction therapy in inclined and sitting traction positions. The model improved upon an old model with additional components to represent the behavior of the intervertebral discs and the posterior ligaments. The simulation result of the new model was compared against the cervical traction data from a radiographic experiment in both positions. The simulation results of the old model and new model were compared to illustrate the improvement. Using the new model, we compared the timing response of cervical traction in the inclined and sitting positions. 相似文献
993.
994.
Kouki Oka Kanako Noguchi Takeo Suga Hiroyuki Nishide Bjorn Winther‐Jensen 《Liver Transplantation》2019,9(6)
The recent discovery that metal‐free polyterthiophene (PTTh) prepared by iodine‐vapor‐assisted polymerization (IVP) can catalyze the hydrogen evolution reaction (HER) when illuminated, and this light‐enhanced electrolysis expresses a non‐Nernstian relation with pH, provides the foundation for further improvement of the photovoltage of the reaction by engineering the band structure of the light‐absorbing polymer. Deviating from an all‐thiophene backbone, using poly(1,4‐di(2‐thienyl))benzene (PDTB) lowers the highest occupied molecular orbital level by ≈0.3 eV compared with polythiophene, and PDTB simultaneously maintains the photoelectrocatalytic properties without an all‐thiophene backbone, resulting in very high conversion rate of 600 mmol(H2) h?1 g?1 at 0 V versus the reversible hydrogen electrode (RHE) at pH 11. PDTB shows the same non‐Nernstian behavior as PTTh with increasing onset potential (versus RHE) at higher pH, and the open circuit potential on PDTB under visible light reaches 1.4 V versus RHE at pH 12. The PDTB photocathode thus produces a photovoltage above the theoretical potential for the complete water‐splitting (1.229 V) and is indeed able to produce hydrogen in a one‐photon‐per‐electron light‐driven water splitting setup with MnOx as the anode at a rate of 6.4 mmol h?1 gPDTB?1. 相似文献
995.
Ayako Yoshida Takeo Tomita Tsutomu Fujimura Chiharu Nishiyama Tomohisa Kuzuyama Makoto Nishiyama 《The Journal of biological chemistry》2015,290(1):435-447
In the biosynthesis of lysine by Thermus thermophilus, the metabolite α-ketoglutarate is converted to the intermediate α-aminoadipate (AAA), which is protected by the 54-amino acid acidic protein LysW. In this study, we determined the crystal structure of LysZ from T. thermophilus (TtLysZ), an amino acid kinase that catalyzes the second step in the AAA to lysine conversion, which was in a complex with LysW at a resolution of 1.85 Å. A crystal analysis coupled with isothermal titration calorimetry of the TtLysZ mutants for TtLysW revealed tight interactions between LysZ and the globular and C-terminal extension domains of the LysW protein, which were mainly attributed to electrostatic forces. These results provided structural evidence for LysW acting as a protecting molecule for the α-amino group of AAA and also as a carrier protein to guarantee better recognition by biosynthetic enzymes for the efficient biosynthesis of lysine. 相似文献
996.
997.
Akiko Matsumoto Hirofumi Arisaka Yuki Hosokawa Shigeki Sakuraba Takeo Sugita Nobuo Umezawa Yuki Kaku Kazu-ichi Yoshida Shun-ichi Kuwana 《Biological research》2015,48(1)
Background
The antiepileptic drugs carbamazepine and gabapentin are effective in treating neuropathic pain and trigeminal neuralgia. In the present study, to analyze the effects of carbamazepine and gabapentin on neuronal excitation in the spinal trigeminal subnucleus caudalis (Sp5c) in the medulla oblongata, we recorded temporal changes in nociceptive afferent activity in the Sp5c of trigeminal nerve-attached brainstem slices of neonatal rats using a voltage-sensitive dye imaging technique.Results
Electrical stimulation of the trigeminal nerve rootlet evoked changes in the fluorescence intensity of dye in the Sp5c. The optical signals were composed of two phases, a fast component with a sharp peak followed by a long-lasting component with a period of more than 500 ms. This evoked excitation was not influenced by administration of carbamazepine (10, 100 and 1,000 μM) or gabapentin (1 and 10 μM), but was increased by administration of 100 μM gabapentin. This evoked excitation was increased further in low Mg2+ (0.8 mM) conditions, and this effect of low Mg2+ concentration was antagonized by 30 μM DL-2-amino-5-phosphonopentanoic acid (AP5), a N-methyl-d-aspartate (NMDA) receptor blocker. The increased excitation in low Mg2+ conditions was also antagonized by carbamazepine (1,000 μM) and gabapentin (100 μM).Conclusion
Carbamazepine and gabapentin did not decrease electrically evoked excitation in the Sp5c in control conditions. Further excitation in low Mg2+ conditions was antagonized by the NMDA receptor blocker AP5. Carbamazepine and gabapentin had similar effects to AP5 on evoked excitation in the Sp5c in low Mg2+ conditions. Thus, we concluded that carbamazepine and gabapentin may act by blocking NMDA receptors in the Sp5c, which contributes to its anti-hypersensitivity in neuropathic pain. 相似文献998.
Sae Tanaka Junko Tanaka Yoshihiro Miwa Daiki D. Horikawa Toshiaki Katayama Kazuharu Arakawa Atsushi Toyoda Takeo Kubo Takekazu Kunieda 《PloS one》2015,10(2)
Tardigrades are able to tolerate almost complete dehydration through transition to a metabolically inactive state, called “anhydrobiosis”. Late Embryogenesis Abundant (LEA) proteins are heat-soluble proteins involved in the desiccation tolerance of many anhydrobiotic organisms. Tardigrades, Ramazzottius varieornatus, however, express predominantly tardigrade-unique heat-soluble proteins: CAHS (Cytoplasmic Abundant Heat Soluble) and SAHS (Secretory Abundant Heat Soluble) proteins, which are secreted or localized in most intracellular compartments, except the mitochondria. Although mitochondrial integrity is crucial to ensure cellular survival, protective molecules for mitochondria have remained elusive. Here, we identified two novel mitochondrial heat-soluble proteins, RvLEAM and MAHS (Mitochondrial Abundant Heat Soluble), as potent mitochondrial protectants from Ramazzottius varieornatus. RvLEAM is a group3 LEA protein and immunohistochemistry confirmed its mitochondrial localization in tardigrade cells. MAHS-green fluorescent protein fusion protein localized in human mitochondria and was heat-soluble in vitro, though no sequence similarity with other known proteins was found, and one region was conserved among tardigrades. Furthermore, we demonstrated that RvLEAM protein as well as MAHS protein improved the hyperosmotic tolerance of human cells. The findings of the present study revealed that tardigrade mitochondria contain at least two types of heat-soluble proteins that might have protective roles in water-deficient environments. 相似文献
999.
Seong-Jin Jang Masako Sato Kei Sato Yutaka Jitsuyama Kaien Fujino Haruhide Mori Ryoji Takahashi Eduardo R. Benitez Baohui Liu Tetsuya Yamada Jun Abe 《PloS one》2015,10(6)
Physical dormancy, a structural feature of the seed coat known as hard seededness, is an important characteristic for adaptation of plants against unstable and unpredictable environments. To dissect the molecular basis of qHS1, a quantitative trait locus for hard seededness in soybean (Glycine max (L) Merr.), we developed a near-isogenic line (NIL) of a permeable (soft-seeded) cultivar, Tachinagaha, containing a hard-seed allele from wild soybean (G. soja) introduced by successive backcrossings. The hard-seed allele made the seed coat of Tachinagaha more rigid by increasing the amount of β-1,4-glucans in the outer layer of palisade cells of the seed coat on the dorsal side of seeds, known to be a point of entrance of water. Fine-mapping and subsequent expression and sequencing analyses revealed that qHS1 encodes an endo-1,4-β-glucanase. A single-nucleotide polymorphism (SNP) introduced an amino acid substitution in a substrate-binding cleft of the enzyme, possibly reducing or eliminating its affinity for substrates in permeable cultivars. Introduction of the genomic region of qHS1 from the impermeable (hard-seeded) NIL into the permeable cultivar Kariyutaka resulted in accumulation of β-1,4-glucan in the outer layer of palisade cells and production of hard seeds. The SNP allele found in the NIL was further associated with the occurrence of hard seeds in soybean cultivars of various origins. The findings of this and previous studies may indicate that qHS1 is involved in the accumulation of β-1,4-glucan derivatives such as xyloglucan and/or β-(1,3)(1,4)-glucan that reinforce the impermeability of seed coats in soybean. 相似文献
1000.
Kimihiko Murase Yasuharu Tabara Hiromu Ito Masahiko Kobayashi Yoshimitsu Takahashi Kazuya Setoh Takahisa Kawaguchi Shigeo Muro Hiroshi Kadotani Shinji Kosugi Akihiro Sekine Ryo Yamada Takeo Nakayama Michiaki Mishima Shuichi Matsuda Fumihiko Matsuda Kazuo Chin 《PloS one》2015,10(10)