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121.
Detecting latitudinal and altitudinal expansion of invasive bamboo Phyllostachys edulis and Phyllostachys bambusoides (Poaceae) in Japan to project potential habitats under 1.5°C–4.0°C global warming 下载免费PDF全文
Kohei Takenaka Takano Kenshi Hibino Ayaka Numata Michio Oguro Masahiro Aiba Hideo Shiogama Izuru Takayabu Tohru Nakashizuka 《Ecology and evolution》2017,7(23):9848-9859
Rapid expansion of exotic bamboos has lowered species diversity in Japan's ecosystems by hampering native plant growth. The invasive potential of bamboo, facilitated by global warming, may also affect other countries with developing bamboo industries. We examined past (1975–1980) and recent (2012) distributions of major exotic bamboos (Phyllostachys edulis and P. bambusoides) in areas adjacent to 145 weather stations in central and northern Japan. Bamboo stands have been established at 17 sites along the latitudinal and altitudinal distributional limit during the last three decades. Ecological niche modeling indicated that temperature had a strong influence on bamboo distribution. Using mean annual temperature and sun radiation data, we reproduced bamboo distribution (accuracy = 0.93 and AUC (area under the receiver operating characteristic curve) = 0.92). These results infer that exotic bamboo distribution has shifted northward and upslope, in association with recent climate warming. Then, we simulated future climate data and projected the climate change impact on the potential habitat distribution of invasive bamboos under different temperature increases (i.e., 1.5°C, 2.0°C, 3.0°C, and 4.0°C) relative to the preindustrial period. Potential habitats in central and northern Japan were estimated to increase from 35% under the current climate (1980–2000) to 46%–48%, 51%–54%, 61%–67%, and 77%–83% under 1.5°C, 2.0°C, 3.0°C, and 4.0°C warming levels, respectively. These infer that the risk areas can increase by 1.3 times even under a 1.5°C scenario and expand by 2.3 times under a 4.0°C scenario. For sustainable ecosystem management, both mitigation and adaptation are necessary: bamboo planting must be carefully monitored in predicted potential habitats, which covers most of Japan. 相似文献
122.
Human somatic stem cells such as mesenchymal stem cells (hMSCs) have the capacity to differentiate into mesenchymal tissue lineages and to alter immune regulatory functions. As such, they hold promise for use in stem cell-based therapies. However, no method is currently available to evaluate the actual differentiation capacity of hMSCs prior to cell transplantation. Previously, we performed a comprehensive glycan profiling of adipose-derived hMSCs using high-density lectin microarray and demonstrated that α2–6-sialylation is a marker of the differentiation potential of these cells. Nevertheless, no information was available about the structural details of these of α2–6-sialylated glycans. Here we used high performance liquid chromatography (HPLC) analysis combined with mass spectrometry (MS) to perform a structural and quantitative glycome analysis targeting both N- and O-glycans derived from early (with differentiation ability) and late (without differentiation ability) passages of adipose tissue-derived hMSCs. Findings in these cells were compared with those from human induced pluripotent stem cells (hiPSCs), human dermal fibroblasts (hFibs) and cartilage tissue-derived chondrocytes. A higher percentage of α2–6-sialylated N-glycans was detected in early passage cells (24–28 % of sialylated N-glycans) compared with late passage cells (13–15 %). A major α2–6-sialylated N-glycan structure detected in adipose-derived hMSCs was that of mono-sialylated biantennary N-glycan. Similar results were obtained for the cartilage tissue-derived chondrocytes, Yub621c (28 % for passage 7 and 5 % for passage 28). In contrast, no significant differences were observed between early and late passage hMSCs with respect to α2–6-sialylated O-glycan percentages. These results demonstrate that levels of α2–6-sialylated N-glycans, but not O-glycans, could be used as markers of the differential potential of hMSCs. 相似文献
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124.
Rapid shoot proliferation was established by adventitious shoot formation on internodal segments. Cross sections of the shoot initiation area were observed microscopically and adventitious shoots were studied under the scanning electron microscope. Shoots were directly formed on the epidermis of internodal segments in vitro without callusing, but not on that of nodal segments with axillary buds. The use of media containing 0.01 – 0.1 mg/l 6-benzyladenine or 0.1 mg /l kinetin and culture under 16 h light increased the number of shoots per segment. The shoots thus obtained were rooted on phytohormone-free Woody Plant or Gamborg B5 solid medium, and were then transferred to soil. When potted, these grew well in a greenhouse. The emetic alkaloid content of adventitious shoots and regenerated plants was determined by HPLC. In vitro shoots cultured in Woody Plant liquid medium supplemented with 0.01 – 0.1 mg/l 6-benzyladenine contained 0.04 – 0.07 % dry wt. emetine and 0.4 – 0.5 % dry wt. cephaeline. One-year old regenerated plants cultivated in a greenhouse demonstrated the same alkaloid content (roots contained 0.82 % dry wt. emetine and 2.16 % dry wt. cephaeline) as the parental plant.Abbreviations MS
Murashige — Skoog (Murashige and Skoog 1962)
- 1/2 MS
half strength MS
- B5
Gamborg B5 (Gamborg et al. 1968)]
- WP
woody plant (Lloyd and McCown 1980)
- RC
root culture (Thomas and Davey 1982)
- HF
phytohormone free
- BA
6-benzyladenine
- Kin
kinetin
- SEM
scanning electron microscopy
- RDF
rotating drum fermenter 相似文献
125.
Yoshiyuki Hakeda Kenji Yoshizawa Marja Hurley Hiroshi Kawaguchi Ken-Ichi Tezuka Kayo Tanaka Takuya Satoh Masayoshi Kumegawa 《Journal of cellular physiology》1994,158(3):444-450
We examined the relationship between signal transduction and the expression of insulin-like growth factor I (IGF-I), IGF-I receptor level, and IGF binding proteins (IGFBPs) in murine clonal osteoblastic MC3T3-E1 cells. 12–O-Tetradecanoylphorbol-13-acetate (TPA), an activator of protein kinase C, decreased the secretion of immunoreactive IGF-I into the medium, whereas dibutyryl cAMP (Bt2cAMP) augmented the secretion In contrast, TPA increased the level of type IIGF receptor on the cells. Furthermore, MC3T3-E1 cells produced and secreted at least three different IGFBPs with molecular masses of 24, 30, and 34 kDa, and the 24-kDa IGFBP was predominant under normal conditions. However, TPA specifically increased the secretion of the 34-kDa IGFBP. The N-terminal amino acid sequence of the purified 34-kDa IGFBP was nearly identical with that of rat IGFBP-2. Furthermore, the 34-kDa IGFBP was immunoreactive to anti-IGFBP-2 antiserum. The level of IGFBP-2 mRNA in the cells was increased by TPA, indicating that the increase in IGFBP-2 secretion results from the stimulation of IGFBP-2 production. In contrast, Bt2cAMP affected neither IGF-l receptor number nor the IGFBP secretion. These results indicate that the production of IGF-l and the expression of IGF-l receptors and IGFBP-2 are up-regulated by the activation of adenylate cyclase and protein kinase C, respectively, in osteoblastic MC3T3-E1 cells. © 1994 Willey-Liss, Inc. 相似文献
126.
A new ophichthid species from the Red Sea of the genus Mixomyrophis,formerly known as Atlantic genus
Ichthyological Research - A new species of worm eel (family Ophichthidae: subfamily Myrophinae), Mixomyrophis longidorsalis sp. nov. is described based on a single specimen [77.0 mm in total length... 相似文献
127.
Multiple points of interaction between retinoic acid and FGF signaling during embryonic axis formation 总被引:7,自引:0,他引:7
Shiotsugu J Katsuyama Y Arima K Baxter A Koide T Song J Chandraratna RA Blumberg B 《Development (Cambridge, England)》2004,131(11):2653-2667
Anteroposterior (AP) patterning of the developing CNS is crucial for both regional specification and the timing of neurogenesis. Several important factors are involved in AP patterning, including members of the WNT and FGF growth factor families, retinoic acid receptors, and HOX genes. We have examined the interactions between FGF and retinoic signaling pathways. Blockade of FGF signaling downregulates the expression of members of the RAR signaling pathway, RARalpha, RALDH2 and CYP26. Overexpression of a constitutively active RARalpha2 rescues the effects of FGF blockade on the expression of XCAD3 and HOXB9. This suggests that RARalpha2 is required as a downstream target of FGF signaling for the posterior expression of XCAD3 and HOXB9. Surprisingly, we found that posterior expression of FGFR1 and FGFR4 was dependent on the expression of RARalpha2. Anterior expression was also altered with FGFR1 expression being lost, whereas FGFR4 expression was expanded beyond its normal expression domain. RARalpha2 is required for the expression of XCAD3 and HOXB9, and for the ability of XCAD3 to induce HOXB9 expression. We conclude that RARalpha2 is required at multiple points in the posteriorization pathway, suggesting that correct AP neural patterning depends on a series of mutually interactive feedback loops among FGFs, RARs and HOX genes. 相似文献
128.
Fujitani N Takegawa Y Ishibashi Y Araki K Furukawa J Mitsutake S Igarashi Y Ito M Shinohara Y 《The Journal of biological chemistry》2011,286(48):41669-41679
129.
130.
Kosuke Matsuo Yang Xiang Hiroshi Nakamura Kayo Masuko Kazuo Yudoh Koji Noyori Kusuki Nishioka Tomoyuki Saito Tomohiro Kato 《Arthritis research & therapy》2007,8(6):R175
Recently, autoantibodies to some citrullinated autoantigens have been reported to be specific for rheumatoid arthritis (RA).
However, an entire profile of and autoimmunity of the citrullinated proteins have been poorly understood. To understand the
profile, we examined citrullinated autoantigens by a proteomic approach and further investigated the significance of citrullination
in antigenicity of one of the autoantigens. Specifically, we detected citrullinated autoantigens in synovial tissue of a patient
with RA by two-dimensional electrophoresis and Western blotting by using pooled sera from five patients with RA and anti-citrulline
antibodies. After identifying the detected autoantigens by mass spectrometry, we investigated the contribution of citrullination
to autoantigenicity by using a recombinant protein with or without citrullination on one of the identified novel citrullinated
autoantigens. As a result, we found 51 citrullinated protein spots. Thirty (58.8%) of these spots were autoantigenic. We identified
13 out of the 30 detected citrullinated autoantigenic proteins. They contained three fibrinogen derivatives and several novel
citrullinated autoantigens (for example, asporin and F-actin capping protein α-1 subunit [CapZα-1]). We further analyzed the
contribution of citrullination to autoantigenicity in one of the detected citrullinated autoantigens, CapZα-1. As a result,
frequencies of autoantibodies to non-citrullinated CapZα-1 were 36.7% in the RA group tested, 10.7% in the osteoarthritis
(OA) group, and 6.5% in healthy donors. On the other hand, those to citrullinated CapZα-1 were 53.3% in the RA group, 7.1%
in the OA group, and 6.5% in the healthy donors. This shows that autoantigenicity of citrullinated or non-citrullinated CapZα-1
is relevant to RA. The antibody titers to the citrullinated CapZα-1 were significantly higher than those to the non-citrullinated
CapZα-1 in 36.7% of patients; however, the other patients showed almost equal antibody titers to both citrullinated and non-citrullinated
CapZα-1. Therefore, the autoantibodies would target citrulline-related and/or citrulline-unrelated epitope(s) of CapZα-1.
In conclusion, we report a profile of citrullinated autoantigens for the first time. Even though citrullination is closely
related to autoantigenicity, citrullination would not always produce autoantigenicity in RA. Citrullinated and non-citrullinated
autoantigens/autoepitopes would have different pathological roles in RA. 相似文献