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41.
42.
Mitsuteru Suzuki Pramod Tandon Masaya Ishikawa Takayuki Toyomasu 《Plant biotechnology reports》2008,2(2):123-131
Vitrification methods are convenient for cryopreserving plant specimens, as the specimens are plunged directly into liquid
nitrogen (LN) from ambient temperatures. However, tissues and species with poor survival are still not uncommon. The development
of vitrification solutions with high survival that cover a range of materials is important. We attempted to develop new vitrification
solutions using bromegrass cells and found that VSL, comprising 20% (w/v) glycerol, 30% (w/v) ethylene glycol, 5% (w/v) sucrose,
10% (w/v) DMSO and 10 mM CaCl2, gave the highest survival following cryopreservation, as determined by fluorescein diacetate staining. However, the cryopreserved
cells showed little regrowth, for unknown reasons. To check its applicability, VSL was used to cryopreserve gentian axillary
buds and the performance was compared with those of conventional vitrification solutions. Excised gentian stem segments with
axillary buds (shoot apices) were two-step precultured with sucrose to induce osmotic tolerance prior to cryopreservation.
Gentian axillary buds cryopreserved using VSL following the appropriate preculturing approach exhibited 78% survival (determined
by the regrowth capacity), which was comparable to PVS2 and PVS1 and far better than PVS3. VSL had a wider optimal incubation
time (20–45 min) than PVS2 and was more suitable for cryopreserving gentian buds. The optimal duration of the first step of
the preculture was 7–11 days, and preculturing with sucrose and glucose gave a much higher survival than fructose and maltose.
VSL was able to vitrify during cooling to LN temperatures, as glass transition and devitrification points were detected in
the warming profiles from differential scanning calorimetry. VSL and its derivative, VSL+, seem to have the potential to be
good alternatives to PVS2 for the cryopreservation of some materials, as exemplified by gentian buds.
Mitsuteru Suzuki, Pramod Tandon and Masaya Ishikawa contributed equally to the work. 相似文献
43.
44.
NFBD1/MDC1 associates with p53 and regulates its function at the crossroad between cell survival and death in response to DNA damage 总被引:4,自引:0,他引:4
Nakanishi M Ozaki T Yamamoto H Hanamoto T Kikuchi H Furuya K Asaka M Delia D Nakagawara A 《The Journal of biological chemistry》2007,282(31):22993-23004
45.
Yuki Sakamoto Jun Yamazaki Takayuki Yamada Jun Yokoyama Yuki Ogura‐Tsujita Masayuki Maki 《Plant Species Biology》2017,32(1):81-86
The diversity of mycorrhizal fungi among four Japanese Cephalanthera (Orchidaceae) species was examined at a total of seven sites, based on sequence variation in nuclear ribosomal DNA. This is the first report to detect mycorrhizal fungi in C. subaphylla. Two patterns of mycorrhizal associations were confirmed from our results. C. falcata has lower fungal specificity, associating with Russulaceae, Sebacinales and Thelephoraceae. By contrast, the three Cephalanthera species C. erecta, C. subaphylla, and C. longifolia were associated mainly with Thelephoraceae fungi. There is no large difference found in mycobionts between green and albino individuals of C. falcata and no distinct preference of Japanese Cephalanthera species for a specific fungal group of Thelephoraceae. 相似文献
46.
Naoki Nishizawa Yoko Kanematsu-Yamaki Masaaki Funata Hiroaki Nagai Ayako Shimizu Hisashi Fujita Junichi Sakamoto Shiro Takekawa Taiji Asami 《Bioorganic & medicinal chemistry letters》2017,27(20):4626-4629
Neuromedin U (NMU) mediates various physiological functions via NMUR1 and NMUR2 receptors. NMUR2 has been considered a promising treatment option for diabetes and obesity. Although NMU-8, a shorter peptide, has potent agonist activity for both receptors, it is metabolically unstable. Therefore, NMU-8 analogs modified with long-chain alkyl moieties via a linker were synthesized. An octadecanoyl analog (17) with amino acid substitutions [αMePhe19, Nle21, and Arg(Me)24] and a linker [Tra-γGlu-PEG(2)] dramatically increased NMUR2 selectivity, with retention of high agonist activity. Subcutaneous administration of 17 induced anorectic activity in C57BL/6J mice. Owing to its high metabolic stability, 17 would be useful in clarifying the physiological role and therapeutic application of NMU. 相似文献
47.
Iwakuma Toshio Hayashi Hidetake Yasuda Ikuko Hanazato Takayuki Takada Kaori 《Hydrobiologia》1990,(1):141-152
Large bag-type (75 m3) and tube-type (105 m3) enclosures were set up in the shallow eutrophic Lake Suwa and were each stocked with exotic planktivorous whitefish (Coregonus lavaretus maraena). The release of whitefish caused the increase in nutrient concentration in the tube-type enclosure whereas no such increase
was observed in the bag-type enclosure. Bottom sediment seemed to be an important source of chironomid food for whitefish.
The proportion of phytoplankton measuring<10μm and 20–40μm, which respectively corresponded toOchromonas spp. andCryptomonas sp., were lower in the fish enclosures than in the control, which might have been caused by high grazing pressure by rotifers.
The predation by whitefish might have affected the species composition of phytoplankton through reducing copepod predation
on rotifers, not through reducing the densities of cladocerans which directly feed on phytoplankton as many investigators
have reported. The phytoplankton biomass was not affected much by the release of fish. Possible reasons are that the increase
in density of rotifers reduced the biomass of available phytoplankton and also that inedible Cyanophyceae were in the decreasing
phase of their seasonal succession and could not increase successfully in spite of elevated nutrient levels. 相似文献
48.
49.
50.
Yoshinari Maeda Kiyoshi Yoshimura Hiroto Matsui Yoshitaro Shindo Takao Tamesa Yukio Tokumitsu Noriaki Hashimoto Yoshihiro Tokuhisa Kazuhiko Sakamoto Kouhei Sakai Yutaka Suehiro Yuji Hinoda Koji Tamada Shigefumi Yoshino Shoichi Hazama Masaaki Oka 《Cancer immunology, immunotherapy : CII》2015,64(8):1047-1056