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991.
Binu Antony Takeshi Fujii Ken'ichi Moto Shogo Matsumoto Mai Fukuzawa Ryo Nakano Sadahiro Tatsuki Yukio Ishikawa 《Insect biochemistry and molecular biology》2009,39(2):90-95
The adzuki bean borer moth, Ostrinia scapulalis, uses a mixture of (E)-11- and (Z)-11-tetradecenyl acetates as a sex pheromone. At a step in the pheromone biosynthetic pathway, fatty-acyl precursors are converted to corresponding alcohols by an enzyme, fatty-acyl reductase (FAR). Here we report the cloning of FAR-like genes expressed in the pheromone gland of female O. scapulalis, and the characterization of a single pheromone-gland-specific FAR (pgFAR) and its functional assay using an insect cell expression system. As many as thirteen FAR-like genes (FAR-I–FAR-XIII) were expressed in the pheromone gland of O. scapulalis; however, only one (FAR-XIII) was pheromone-gland-specific. The deduced amino acid sequence of FAR-XIII predicted a 462-aa protein with a conserved NAD(P)H-binding motif in the N-terminal region, showing overall identity of 34% with the pgFAR of Bombyx mori. A functional assay using Sf9 cells transfected with an expression vector containing the open reading frame of the FAR-XIII gene has proven that FAR-XIII protein has the ability to convert a natural substrate, (Z)-11-tetradecenoic acid, to a corresponding alcohol, (Z)-11-tetradecenol. 相似文献
992.
Hiroshi Morita Yuichiro Tomizawa Jun Deguchi Tokio Ishikawa Hiroko Arai Kazumasa Zaima Takahiro Hosoya Yusuke Hirasawa Takayuki Matsumoto Katsuo Kamata Wiwied Ekasari Aty Widyawaruyanti Tutik Sri Wahyuni Noor Cholies Zaini Toshio Honda 《Bioorganic & medicinal chemistry》2009,17(24):8234-8240
Cassiarin A 1, a tricyclic alkaloid, isolated from the leaves of Cassia siamea (Leguminosae), shows powerful antimalarial activity against Plasmodium falciparum in vitro as well as P. berghei in vivo, which may be valuable leads for novel antimalarials. Interactions of parasitized red blood cells (pRBCs) with endothelium in aorta are especially important in the processes contribute to the pathogenesis of severe malaria. Nitric oxide (NO) reduces endothelial expression of receptors/adhesion molecules used by pRBC to adhere to vascular endothelium, and reduces cytoadherence of pRBC to vascular endothelium. Cassiarin A 1 showed vasorelaxation activity against rat aortic ring, which may be related with NO production. A series of a hydroxyl and a nitrogen-substituted derivatives and a dehydroxy derivative of 1 have been synthesized as having potent antimalarials against P. falciparum with vasodilator activity, which may reduce cytoadherence of pRBC to vascular endothelium. Cassiarin A 1 exhibited a potent antimalarial activity and a high selectivity index in vitro, suggesting that the presence of a hydroxyl and a nitrogen atom without any substituents may be important to show antimalarial activity. Relative to cassiarin A, a methoxy derivative showed more potent vasorelaxant activity, although it did not show improvement for inhibition of P. falciparum in vitro. These cassiarin derivatives may be promising candidates as antimalarials with different mode of actions. 相似文献
993.
994.
995.
Pan Y Iwata F Wang D Muraguchi M Ooga K Ohmoto Y Takai M Cho G Kang J Shono M Li XJ Okamura K Mori T Ishikawa Y 《Biochimica et biophysica acta》2009,1790(1):49-56
BACKGROUND: It is unknown whether AQP5 and lipid rafts are released into human unstimulated (resting) saliva and saliva in response to secretagogues. METHODS: In order to quantitate the salivary concentration of AQP5, we produced a polyclonal antibody for human AQP5 and developed an enzyme-like immunosorbent assay (ELISA). RESULTS: AQP5 and lipid rafts were identified in human resting saliva. The amount of AQP5 in resting saliva showed a diurnal variation with high levels during waking hours, and an age-related decrease in AQP5 was coincident with the volume of resting saliva. Cevimeline, a muscarinic acetylcholine receptor (mAChR) agonist, induced the release of AQP5 with lipid rafts, amylase, mucin, and lysozyme. Changes in saliva AQP5 levels after cevimeline administration occurred simultaneously with changes in saliva flow rates. Confocal microscopy revealed that AQP5 was located in the apical plasma membrane and showed a diffuse pattern in parotid glands under resting conditions. Following cevimeline administration, AQP5 was predominantly associated with the APM and was localized in the lumen. GENERAL SIGNIFICANCE: AQP5 and lipid rafts were released with salivary proteins from human salivary glands by the stimulation of M3 mAChRs, and that changes in saliva AQP5 levels can be used as an indicator of salivary flow rate and also as a useful index of M3 mAChR agonist's action on human salivary glands. 相似文献
996.
Yoshihiro Ishikawa Jackie Wirz Janice A. Vranka Kazuhiro Nagata Hans Peter B?chinger 《The Journal of biological chemistry》2009,284(26):17641-17647
The rough endoplasmic reticulum-resident protein complex consisting of prolyl 3-hydroxylase 1 (P3H1), cartilage-associated protein (CRTAP), and cyclophilin B (CypB) can be isolated from chick embryos on a gelatin-Sepharose column, indicating some involvement in the biosynthesis of procollagens. Prolyl 3-hydroxylase 1 modifies a single proline residue in the α chains of type I, II, and III collagens to (3S)-hydroxyproline. The peptidyl-prolyl cis-trans isomerase activity of cyclophilin B was shown previously to catalyze the rate of triple helix formation. Here we show that cyclophilin B in the complex shows peptidyl-prolyl cis-trans isomerase activity and that the P3H1·CRTAP·CypB complex has another important function: it acts as a chaperone molecule when tested with two classical chaperone assays. The P3H1·CRTAP·CypB complex inhibited the thermal aggregation of citrate synthase and was active in the denatured rhodanese refolding and aggregation assay. The chaperone activity of the complex was higher than that of protein-disulfide isomerase, a well characterized chaperone. The P3H1·CRTAP·CypB complex also delayed the in vitro fibril formation of type I collagen, indicating that this complex is also able to interact with triple helical collagen and acts as a collagen chaperone. 相似文献
997.
Thais Graziela Donegá França Larissa Lumi Watanabe Ishikawa Sofia Fernanda Gonçalves Zorzella-Pezavento Fernanda Chiuso-Minicucci Clara Pires Fujiara Guerino de Lourdes Ribeiro de Souza Maria da Cunha Alexandrina Sartori 《BMC microbiology》2009,9(1):240-7
Background
Staphylococcus aureus methicillin-resistant (MRSA) has been frequently isolated from endotracheal and lung puncture aspirates in malnourished children with pneumonia. In this work we evaluated the susceptibility of undernourished BALB/c mice and its ability to mount a protective immunity against MRSA with emphasis on the lung involvement. 相似文献998.
Tomonari Hirano Toshinari Godo Kazumitsu Miyoshi Keiko Ishikawa Masaya Ishikawa Masahiro Mii 《Plant biotechnology reports》2009,3(1):103-109
In this study we established reliable methods for conservation of seeds of Phaius tankervilleae as an orchid genetic resource. The seeds, which were dehydrated to 5% water content and preserved at 4°C, showed no decrease
in viability and germinability after three months. After storage for six months, however, the seeds showed a drastic decrease
in germinability, even though survival rate was high. For long-term preservation of seeds of P. tankervilleae, cryopreservation is applied to the freshly harvested seeds. When the seeds were cryopreserved by the vitrification method
for up to 12 months there was no apparent deterioration effect of storage time. These results indicate that cryopreservation
by the vitrification method is useful for long-term conservation of P. tankervilleae seeds, which are difficult to preserve for more than three months under dry and low-temperature conditions. 相似文献
999.
Buxiang Sun Koji Wakame Eri Sato Hiroshi Nishioka Okezie I. Aruoma Hajime Fujii 《Cancer epidemiology》2009,33(3-4):293-299
Background: Active hexose correlated compound (AHCC) (a mixture of polysaccharides, amino acids, lipids and minerals derived from cultured mycelia of a Basidiomycete mushroom, Lentinula edodes) was used to assess amelioration of alopecia (hair loss) caused by cytosine arabinoside (Ara-C) and modulation of liver injury caused by single doses 6-mercaptopurine (6-MP) plus methotrexate (MTX). Methods: Follicular integrity and hair growth was assessed in male and female SD neonatal rats (8 days old) treated with a single dose of Ara-C (30 mg/kg/day, i.p.) and AHCC (500 mg/kg/day, p.o.) for 7 consecutive days. The side effects of a single oral dose of 6-MP (2.5 mg/kg body weight) plus MTX (30 mg/kg body weight) and their amelioration by treatment with AHCC (1000 mg/kg body weight) for 28 days were assessed in male ddY mice (8 weeks old). Results: Of the Ara-C treated rats 71.4% showed severe alopecia and 28.6% showed moderate alopecia. However, the AHCC (p.o.)-treated Ara-C group was significantly protected from alopecia. Ara-C treated rats had profound loss of hair follicles but the Ara-C plus AHCC-treated group had mild losses of follicles. AHCC supplementation to the 6-MP- and MTX-treated mice significantly increased body weight, erythrocytes, leukocytes and serum albumin, improved liver hypertrophy and degeneration, normalized the activities of serum glutamic oxaloacetic transaminase (sGOT) and serum glutamic pyruvic transaminase (sGPT), and enhanced liver drug-metabolizing enzymes. Conclusion: Co-administration of AHCC significantly reduced the side effects associated with Ara-C, 6-MP and MTX. However, the molecular mechanism for AHCC activity and its clinical integrity for use needs defining. 相似文献
1000.
Shuji Toda Kazuyoshi Uchihashi Shigehisa Aoki Emiko Sonoda Fumio Yamasaki Meihua Piao Akifumi Ootani Nobuhisa Yonemitsu Hajime Sugihara 《Organogenesis》2009,5(2):50-56
Adipose tissue consists of mature adipocytes, preadipocytes and mesenchymal stem cells (MSCs), but a culture system for analyzing their cell types within the tissue has not been established. We have recently developed “adipose tissue-organotypic culture system” that maintains unilocular structure, proliferative ability and functions of mature adipocytes for a long term, using three-dimensional collagen gel culture of the tissue fragments. In this system, both preadipocytes and MSCs regenerate actively at the peripheral zone of the fragments. Our method will open up a new way for studying both multiple cell types within adipose tissue and the cell-based mechanisms of obesity and metabolic syndrome. Thus, it seems to be a promising model for investigating adipose tissue biology and regeneration. In this article, we introduce adipose tissue-organotypic culture, and propose two theories regarding the mechanism of tissue regeneration that occurs specifically at peripheral zone of tissue fragments in vitro.Key words: adipose tissue-organotypic culture, three-dimensional, tissue fragments, peripheral zone, central zone, mature adipocytes, preadipocytes (immature adipocytes), mesenchymal stem cells, adipokines, tissue regeneration 相似文献