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991.
992.
Mohammad Monir Shah Yoshihiro Miyamoto Yoshihito Yamada Hirotaka Yamashita Hiroyuki Tanaka Takayuki Ezaki Hiroichi Nagai Naoki Inagaki 《Microbiology and immunology》2010,54(9):523-533
Oral supplementation of lactic acid bacteria is a potential approach to the prevention and manipulation of allergic diseases such as atopic dermatitis. Our previous report showed that heat‐killed Lactobacillus acidophilus strain L‐92 (L‐92) possessed anti‐allergic properties, although its physiological function in atopic dermatitis has largely remained undefined. To evaluate the anti‐allergic efficacy of L‐92, we used four experimental animal models with the major features of atopic dermatitis and compared the results to those of clinically active drugs. ICR mice were passively sensitized by anti‐dinitrophenyl mouse monoclonal IgE for passive cutaneous anaphylaxis (PCA), and BALB/c mice were actively sensitized by ovalbumin for active cutaneous anaphylaxis (ACA). Allergic reaction was induced by repeated exposure to 2,4‐dinitroflurobenzene (DNFB) and mite (Dermatophagoides farinae) fecal allergen, in BALB/c and NC/Nga mice, respectively. Orally administrated L‐92 significantly inhibited the vascular permeability increase in both PCA and ACA, and the elevation of ovalbumin‐specific IgE titer in ACA. Moreover, repeated applications of DNFB and mite fecal antigen onto the BALB/c and NC/Nga mouse ear, respectively, caused clinical symptoms similar to atopic dermatitis such as ear swelling, scratching behavior and elevation of total serum IgE levels that were also moderately suppressed by L‐92. In addition, L‐92 treated mice exhibited lower levels of mast cells, eosinophil infiltration and Th1/Th2 cytokine expression. Our results, therefore, suggest that oral administration of L‐92 might be useful for alleviating allergic symptoms. 相似文献
993.
994.
Tadashi Tatsumi Chiyuki Awahara Hiromi Naka Saburo Aimoto Hiroyuki Konno Kazuto Nosaka Kenichi Akaji 《Bioorganic & medicinal chemistry》2010,18(7):2720-2727
Effects of retro-inverso (RI) modifications of HTLV-1 protease inhibitors containing a hydroxyethylamine isoster backbone were clarified. Construction of the isoster backbone was achieved by a stereoselective aldol reaction. Four diastereomers with different configurations at the isoster hydroxyl site and the scissile site substituent were synthesized. Inhibitory activities of the new inhibitors suggest that partially modified RI inhibitors would interact with HTLV-1 protease in the same manner as the parent hydroxyethylamine inhibitor. 相似文献
995.
Mark A. Arbing Samuel K. Handelman Alexandre P. Kuzin Grégory Verdon Chi Wang Min Su Francesca P. Rothenbacher Mariam Abashidze Mohan Liu Jennifer M. Hurley Rong Xiao Thomas Acton Masayori Inouye Gaetano T. Montelione Nancy A. Woychik John F. Hunt 《Structure (London, England : 1993)》2010,18(8):996-1010
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997.
998.
Makiko Kosugi Yuya Katashima Shimpei Aikawa Yukiko Tanabe Sakae Kudoh Yasuhiro Kashino Hiroyuki Koike Kazuhiko Satoh 《Journal of phycology》2010,46(3):466-476
The terrestrial cyanobacterium Nostoc commune Vaucher ex Bornet et Flahault occurs worldwide, including in Japan and on the Antarctic continent. The terrestrial green alga Prasiola crispa (Lightf.) Kütz. is also distributed in Antarctica. These two species need to acclimate to the severe Antarctic climate including low ambient temperature and desiccation under strong light conditions. To clarify this acclimation process, the physiological characteristics of the photosynthetic systems of these two Antarctic terrestrial organisms were assessed. The relative rate of photosynthetic electron flow in N. commune collected in Japan and in Antarctica reached maxima at 900 and 1,100 μmol photons · m?2 · s?1, respectively. The difference seemed to reflect the presence of high amounts of UV‐absorbing substances within the Antarctic cyanobacterium. On the other hand, the optimal temperatures for photosynthesis at the two locations were 30°C–35°C and 20°C–25°C, respectively. This finding suggested a decreased photosynthetic thermotolerance in the Antarctic strain. P. crispa exhibited desiccation tolerance and dehydration‐induced quenching of PSII fluorescence. Re‐reduction of the photooxidized PSI reaction center, P700, was also inhibited at fully dry states. Photosynthetic electron flow in P. crispa reached a maximum at 20°C–25°C and at a light intensity of 700 μmol photons ? m?2 ? s?1. Interestingly, the osmolarity of P. crispa cells suggested that photosynthesis is performed using water absorbed in a liquid form rather than water absorbed from the air. Overall, these data suggest that these two species have acclimated to optimally photosynthesize under conditions of the highest light intensity and the highest temperature for their habitat in Antarctica. 相似文献
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1000.
Katsuko Shiraya Taku Hirata Ryo Hatano Shushi Nagamori Pattama Wiriyasermkul Promsuk Jutabha Mitsunobu Matsubara Shigeaki Muto Hidekazu Tanaka Shinji Asano Naohiko Anzai Hitoshi Endou Akira Yamada Hiroyuki Sakurai Yoshikatsu Kanai 《The Journal of biological chemistry》2010,285(29):22141-22151
We identified a novel prostaglandin (PG)-specific organic anion transporter (OAT) in the OAT group of the SLC22 family. The transporter designated OAT-PG from mouse kidney exhibited Na+-independent and saturable transport of PGE2 when expressed in a proximal tubule cell line (S2). Unusual for OAT members, OAT-PG showed narrow substrate selectivity and high affinity for a specific subset of PGs, including PGE2, PGF2α, and PGD2. Similar to PGE2 receptor and PGT, a structurally distinct PG transporter, OAT-PG requires for its substrates an α-carboxyl group, with a double bond between C13 and C14 as well as a (S)-hydroxyl group at C15. Unlike the PGE2 receptor, however, the hydroxyl group at C11 in a cyclopentane ring is not essential for OAT-PG substrates. Addition of a hydroxyl group at C19 or C20 impairs the interaction with OAT-PG, whereas an ethyl group at C20 enhances the interaction, suggesting the importance of hydrophobicity around the ω-tail tip forming a “hydrophobic core” accompanied by a negative charge, which is essential for substrates of OAT members. OAT-PG-mediated transport is concentrative in nature, although OAT-PG mediates both facilitative and exchange transport. OAT-PG is kidney-specific and localized on the basolateral membrane of proximal tubules where a PG-inactivating enzyme, 15-hydroxyprostaglandin dehydrogenase, is expressed. Because of the fact that 15-keto-PGE2, the metabolite of PGE2 produced by 15-hydroxyprostaglandin dehydrogenase, is not a substrate of OAT-PG, the transport-metabolism coupling would make unidirectional PGE2 transport more efficient. By removing extracellular PGE2, OAT-PG is proposed to be involved in the local PGE2 clearance and metabolism for the inactivation of PG signals in the kidney cortex. 相似文献