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71.
Matsumoto Y Suzuki S Nozoye T Yamakawa T Takashima Y Arakawa T Tsuji N Takaiwa F Hayashi Y 《Transgenic research》2009,18(2):185-192
Cereal crops such as maize and rice are considered attractive for vaccine production and oral delivery. Here, we evaluated
the rice Oryza sativa for production of As16—an antigen protective against the roundworm Ascaris suum. The antigen was produced as a chimeric protein fused with cholera toxin B subunit (CTB), and its expression level in the
endosperm reached 50 μg/g seed. Feeding the transgenic (Tg) rice seeds to mice elicited an As16-specific serum antibody response
when administered in combination with cholera toxin (CT) as the mucosal adjuvant. Although omitting the adjuvant from the
vaccine formulation resulted in failure to develop the specific immune response, subcutaneous booster immunization with bacterially
expressed As16 induced the antibody response, indicating priming capability of the Tg rice. Tg rice/CT-fed mice orally administered
A. suum eggs had a lower lung worm burden than control mice. This suggests that the rice-delivered antigen functions as a prophylactic
edible vaccine for controlling parasitic infection in animals. 相似文献
72.
Matsuda H Yoshida K Miyagawa K Nemoto Y Asao Y Yoshikawa M 《Bioorganic & medicinal chemistry letters》2006,16(6):1567-1573
The methanolic extract and its alkaloid fraction from the rhizomes of Nuphar pumilum showed cytotoxic effects on human leukemia cell (U937), mouse melanoma cell (B16F10), and human fibroblast (HT1080). Dimeric sesquiterpene thioalkaloids with the 6-hydroxyl group (6-hydroxythiobinupharidine, 6,6'-dihydroxythiobinupharidine, 6-hydroxythionuphlutine B) showed substantial cytotoxic activity at a concentration of 10 microM, but dimeric sesquiterpene thioalkaloids lacking the 6-hydroxyl group (thiobinupharidine, thionuphlutine B, 6'-hydroxythionuphlutine B, neothiobinupharidine, thionuphlutine B beta-sulfoxide, and neothiobinupharidine beta-sulfoxide) and monomeric sesquiterpene alkaloids (nupharidine, 7-epideoxynupharidine, and nupharolutine) showed weak activity. Next, apoptosis-inducing activity of a principal active constituent, 6-hydroxythiobinupharidine, on U937 was examined using morphological observation and DNA fragmentation assay (TUNEL method). Apoptosis of U937 was immediately observed within 1 h after treatment of 6-hydroxythiobinupharidine at 2.5-10 microM. 相似文献
73.
Kubota K Niinuma Y Kaneko M Okuma Y Sugai M Omura T Uesugi M Uehara T Hosoi T Nomura Y 《Journal of neurochemistry》2006,97(5):1259-1268
Endoplasmic reticulum (ER) stress is defined as an accumulation of unfolded proteins in the endoplasmic reticulum. 4-phenylbutyrate (4-PBA) has been demonstrated to promote the normal trafficking of the DeltaF508 cystic fibrosis transmembrane conductance regulator (CFTR) mutant from the ER to the plasma membrane and to restore activity. We have reported that 4-PBA protected against cerebral ischemic injury and ER stress-induced neuronal cell death. In this study, we revealed that 4-PBA possesses chemical chaperone activity in vitro, which prevents the aggregation of denatured alpha-lactalbumin and bovine serum albumin (BSA). Furthermore, we investigated the effects of 4-PBA on the accumulation of Parkin-associated endothelin receptor-like receptor (Pael-R) pathologically relevant to the loss of dopaminergic neurons in autosomal recessive juvenile parkinsonism (AR-JP). Interestingly, 4-PBA restored the normal expression of Pael-R protein and suppressed ER stress induced by the overexpression of Pael-R. In addition, we showed that 4-PBA attenuated the activation of ER stress-induced signal transduction pathways and subsequent neuronal cell death. Moreover, 4-PBA restored the viability of yeasts that fail to induce an ER stress response under ER stress conditions. These results suggest that 4-PBA suppresses ER stress by directly reducing the amount of misfolded protein, including Pael-R accumulated in the ER. 相似文献
74.
Shoot cultures of Tamarix tetrandra on Linsmaier–Skoog (LS) agar medium with 30 g l−1 sucrose, 2.13 mg l−1 indoleacetic acid and 2.25 mg l−1 benzyl adenine produced ellagitannins found in intact plants of the Tamaricaceae. This was demonstrated by the isolation of 14 monomeric–tetrameric ellagitannins from the aq. Me2CO extract of the cultured tissues. This is the first report on the production of ellagitannin tetramers by plant tissue culture. The effects of light and certain medium constituents on tissue growth and ellagitannin production were examined. The contents of representative tannins of different types [i.e., tellimagrandin II (monomer), hirtellin A (linear GOG-type dimer), hirtellin B (hellinoyl-type dimer), hirtellin C (macrocyclic-type dimer), and hirtellin T1 (linear GOG-type trimer)] in the resultant tissues in response to these factors were estimated by HPLC, and the optimal condition for production of these tannins were established. Shoots cultured on LS hormone-free medium promoted root development, and regenerated plants could adapt to ordinary soil and climate. Acclimatized and intact T. tetrandra plants that were collected in November and May, respectively, demonstrated seasonal differences in individual ellagitannin contents. HPLC comparison of individual ellagitannin contents in different plant materials (i.e., leaves, stems, and roots) of intact T. tetrandra plants is also reported. The results are discussed with respect to cellular deposition and biosynthetic relationship of tannins. 相似文献
75.
76.
Masahiro Myojo Daisuke Nagata Daishi Fujita Arihiro Kiyosue Masao Takahashi Hiroshi Satonaka Yoshiyuki Morishita Tetsu Akimoto Ryozo Nagai Issei Komuro Yasunobu Hirata 《PloS one》2014,9(5)
Because endothelial nitric oxide synthase (eNOS) has anti-inflammatory and anti-arteriosclerotic functions, it has been recognized as one of the key molecules essential for the homeostatic control of blood vessels other than relaxation of vascular tone. Here, we examined whether telmisartan modulates eNOS function through its pleiotropic effect. Administration of telmisartan to mice significantly increased the phosphorylation level of eNOS (Ser1177) in the aortic endothelium, but administration of valsartan had no effect. Similarly, telmisartan treatment of human umbilical vein endothelial cells significantly increased the phosphorylation levels of AMP-activated protein kinase (Thr172) and eNOS and the concentration of intracellular guanosine 3′,5′-cyclic monophosphate (cGMP). Furthermore, pretreatment with a p38 mitogen-activated protein kinase (p38 MAPK) inhibitor suppressed the increased phosphorylation level of eNOS and intracellular cGMP concentration. These data show that telmisartan increases eNOS activity through Ser1177 phosphorylation in vascular endothelial cells mainly via p38 MAPK signaling. 相似文献
77.
Breeding ecology of the stream goby,Rhinogobius sp. LD (Large Dark), was investigated under natural conditions. Males selectively courted females of similar size to lead
them to the nests, whereas females followed courting males preferentially when the relative male size was greater. Male-male
competition for a female was relatively infrequent and not severe. Developmental stages of eggs and egg numbers in one nest
indicated that males receive 1–3 clutches during one breeding cycle. Males guarding multiple clutches frequently ate some
of the eggs, but those guarding single clutches rarely did so. Gravid females in the nest also frequently cannibalized eggs
laid by a previous female, probably in order to extend the area available for egg deposition. Mate choice in this species
is discussed in relation to paternal ability, limitation of available spawning area and the female-biased sex ratio. 相似文献
78.
Synopsis The frequency and origin of intraspecific brood-mixing in the biparental cichlid fishPerissodus microlepis were investigated by the cohort analysis of schooling young and the underwater observation of guarding parents. The cohort analysis showed that brood-mixing started from the early guarding state when the young were smaller than 10 mm standard length and nearly all schools of young larger than 16 mm contained alien young from up to 6 broods. Brood farming-out of this fish, which was originally proposed to be a way adopted only by a deserted parent, was performed also by paired parents. We suggest that brood-mixing inP. microlepis is attributed mainly to brood farming-out by paired and deserted parents. 相似文献
79.
Horike N Sakoda H Kushiyama A Ono H Fujishiro M Kamata H Nishiyama K Uchijima Y Kurihara Y Kurihara H Asano T 《The Journal of biological chemistry》2008,283(49):33902-33910
80.
Up-regulation of sodium-dependent glucose transporter by interaction with heat shock protein 70 总被引:1,自引:0,他引:1
Heat shock stress induces some heat shock proteins, including Hsp70, and activates sodium-dependent glucose transport in porcine renal LLC-PK(1) cells, but its mechanisms have not been described in detail. We investigated whether sodium-dependent glucose transporter (SGLT1) interacts with Hsp70 to increase SGLT1 activity. Heat shock stress increased SGLT1 activity without changing SGLT1 expression. The increase of SGLT1 activity was completely inhibited by an anti-transforming growth factor-beta1 (TGF-beta1) antibody. Instead of heat shock stress, TGF-beta1 increased SGLT1 activity dose- and time-dependently without changing SGLT1 expression. We found that the amount of Hsp70 immunoprecipitated from TGF-beta1-treated cells with an anti-SGLT1 antibody was higher than that of the control cells. Transfection of an anti-Hsp70 antibody into the cells inhibited the increase of SGLT1 activity. With confocal laser microscopy, both SGLT1 and Hsp70 was localized near the apical membrane in the TGF-beta1-treated cells, and an anti-Hsp70 antibody disturbed this localization. Furthermore, we clarified that an anti-Hsp70 antibody inhibited interaction of SGLT1 with Hsp70 in vitro. These results suggest that Hsp70 forms a complex with SGLT1 and increases the expression level of SGLT1 in the apical membrane, resulting in up-regulation of glucose uptake. 相似文献