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151.
Ryosuke Makabe Hiroshi Hattori Makoto Sampei Yuya Ota Mitsuo Fukuchi Louis Fortier Hiroshi Sasaki 《Polar Biology》2010,33(2):257-270
Time-series sediment traps were deployed at six mooring sites in the southeastern Beaufort Sea from October 2003 to August
2004 during the cruise of the Canadian research vessel Amundsen within the framework of the Canadian Arctic Shelf Exchange
Study (CASES). Trap-collected zooplankton (TCZ) at around 200 m water depth was dominated by copepods accounting for 74–93%
of the total abundance throughout the year with increase in abundance at all sites during the fall. Seven distinct TCZ groups
were identified through cluster analysis. Two marked seasonal shifts in TCZ composition from late fall to early winter and
from spring to early summer were revealed at five sites at 200 m depth. The zooplankton was dominated by Oncaea spp., pteropods, and copepod nauplii in the late fall cluster and in the winter cluster, and by copepod nauplii in the summer
cluster. A significant change in water temperature, salinity, and sea ice concentration was observed only with the spring–summer
shift. The cluster analysis also revealed that TCZ composition at 200 m at a station located in the Cape Bathurst Polynya
was markedly different from those at other sites through the study period by being characterized by the dominance of various
copepodite stages of Metridia longa. This was probably due to a less prolonged period of sea ice cover, which provides favorable food conditions for the zooplankton
community. 相似文献
152.
Perturbations in protein folding and degradation are key pathological mechanisms in neurodegenerative diseases, including Parkinson's disease (PD). Recent evidence suggests that mishandling of proteins may play an important role in the pathogenesis of PD. We have utilized medaka fish to monitor the effects of injecting neurotoxins into the CSF space. In this study, ammonium chloride, tunicamycin, and lactacystin were tested for their ability to disturb lysosomal proteolysis, N-glycosylation in the endoplasmic reticulum, and proteasomal degradation, respectively. All of the substances tested induced selective loss of dopaminergic neurons, movement disorders and inclusion bodies. Among them, the features of the inclusion bodies that developed after ammonium chloride injection mimicked those of PD: co-localization of ubiquitin and phosphorylated α-synuclein, as well as the presence of LC3 protein in the inclusion bodies. Our study demonstrated that medaka fish are useful for examining the effects of environmental toxins and lysosome inhibition, and lysosome inhibitors may be factors in the development of PD. 相似文献
153.
Yamazaki Y Abe K Toma T Nishikawa M Ozawa H Okuda A Araki T Oda S Inoue K Shibuya K Staels B Fruchart JC 《Bioorganic & medicinal chemistry letters》2007,17(16):4689-4693
A combination of benzoxazole, phenoxyalkyl side chain, and phenoxybutyric acids was identified as a highly potent and selective human peroxisome proliferator-activated receptor alpha (PPARalpha) agonist. The synthesis, structure-activity relationship (SAR) studies, and in vivo activities of the representative compounds are described. 相似文献
154.
Inoue Kanako Takemura Chika Senuma Wakana Maeda Hidefumi Kai Kenji Kiba Akinori Ohnishi Kouhei Tsuzuki Masayuki Hikichi Yasufumi 《Journal of plant research》2023,136(1):19-31
Journal of Plant Research - The soil-borne Gram-negative β-proteobacterium Ralstonia solanacearum species complex (RSSC) infects tomato roots through the wounds where secondary roots emerge,... 相似文献
155.
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158.
Kynet Kong So Makabe Valentine Otang Ntui Raham Sher Khan Ikuo Nakamura 《Plant biotechnology reports》2014,8(2):151-159
Fusarium wilt is a soil-borne disease causing substantial yield losses in various crops and vegetables. We have previously reported the synthetic chitinase (NIC) gene (1.2 kb), in which codon usage of fungus, replaced with that of plant, conferred resistance against Botrytis cinerea. In this study, the NIC or GUS gene was linked to two root-specific promoters, LjNRT2 or AtNRT2.1 (nitrate transporter 2), derived from Lotus japonica and Arabidopsis thaliana, respectively. Transgenic tobacco lines expressing LjNRT2-GUS and LjNRT2-NIC, and tomato lines expressing AtNRT2.1-NIC, were produced by Agrobacterium-mediated transformation. GUS histochemical staining was observed in vascular regions of the roots but was conspicuously absent in the leaves of transgenic plants. Western blot analysis showed the production of NIC proteins in the roots but not in the leaves of transgenic tobacco and tomato lines. These results indicate that LjNRT2 and AtNRT2.1 promoters expressed transgenes in a root-specific manner. When in vitro whole plant resistance assay against Fusarium oxysporum was conducted, transgenic plants showed increased levels of resistance compared to non-transgenic plants. Antifungal activities of the root extract against spore germination of F. oxysporum showed lower CFU (colony-forming unit) than those of the leaf extract. Root colonization assay against F. oxysporum showed much lower CFU values in the roots of transgenic plants than in those of non-transgenic plants. These results suggest that NIC gene triggered by the root-specific promoters successfully expressed only in the roots and conferred increased levels of resistance against the root pathogen, F. oxysporum. 相似文献
159.
Kato I Niwa A Heike T Fujino H Saito MK Umeda K Hiramatsu H Ito M Morita M Nishinaka Y Adachi S Ishikawa F Nakahata T 《PloS one》2011,6(11):e27042
In acute lymphoblastic leukemia (ALL) patients, the bone marrow niche is widely known to be an important element of treatment response and relapse. Furthermore, a characteristic liver pathology observed in ALL patients implies that the hepatic microenvironment provides an extramedullary niche for leukemic cells. However, it remains unclear whether the liver actually provides a specific niche. The mechanism underlying this pathology is also poorly understood. Here, to answer these questions, we reconstituted the histopathology of leukemic liver by using patients-derived primary ALL cells into NOD/SCID/Yc (null) mice. The liver pathology in this model was similar to that observed in the patients. By using this model, we clearly demonstrated that bile duct epithelial cells form a hepatic niche that supports infiltration and proliferation of ALL cells in the liver. Furthermore, we showed that functions of the niche are maintained by the SDF-1/CXCR4 axis, proposing a novel therapeutic approach targeting the extramedullary niche by inhibition of the SDF-1/CXCR4 axis. In conclusion, we demonstrated that the liver dissemination of leukemia is not due to nonselective infiltration, but rather systematic invasion and proliferation of leukemic cells in hepatic niche. Although the contribution of SDF-1/CXCR4 axis is reported in some cancer cells or leukemic niches such as bone marrow, we demonstrated that this axis works even in the extramedullary niche of leukemic cells. Our findings form the basis for therapeutic approaches that target the extramedullary niche by inhibiting the SDF-1/CXCR4 axis. 相似文献
160.
Yamada M Ihara M Okamoto Y Maki T Washida K Kitamura A Hase Y Ito H Takao K Miyakawa T Kalaria RN Tomimoto H Takahashi R 《PloS one》2011,6(1):e16567