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101.
Ikeda Y Yonemitsu Y Kataoka C Kitamoto S Yamaoka T Nishida K Takeshita A Egashira K Sueishi K 《American journal of physiology. Heart and circulatory physiology》2002,283(5):H2021-H2028
Monocyte/macrophage chemoattractant protein-1 (MCP-1), a potent chemoattractant chemokine and an activator for mononuclear cells, may play a role in the initiation and/or progression of pulmonary hypertension (PH). To determine whether blockade of a systemic MCP-1 signal pathway in vivo may prevent PH, we intramuscularly transduced a naked plasmid encoding a 7-NH(2) terminus-deleted dominant negative inhibitor of the MCP-1 (7ND MCP-1) gene in monocrotaline-induced PH. We also simultaneously gave a duplicate transfection at 2-wk intervals or skeletal muscle-directed in vivo electroporation (EP) to evaluate whether a longer or higher expression might be more effective. The intramuscular reporter gene expression was enhanced 10 times over that by EP than by simple injection, and a significant 7ND MCP-1 protein in plasma was detected only in the EP group. 7ND MCP-1 gene transfer significantly inhibited the progression of MCT-induced PH as evaluated by right ventricular systolic pressure, right ventricular hypertrophy, medial hypertrophy of pulmonary arterioles, and mononuclear cell infiltration into the lung. Differential effects of longer or higher transgene expression were not apparent. Although the in vivo kinetics of 7ND MCP-1 gene therapy should be studied further, these encouraging results suggest that an anti-inflammatory strategy via blockade of the MCP-1 signal pathway may be an alternative approach to treat subjects with PH. 相似文献
102.
Akira Tanaka 《Journal of insect physiology》1982,28(10):813-821
Effects of repeated carbon-dioxide anaesthesia during larval development on the number of moults, larval duration, and the body size of resulting adults were investigated. Concentration of carbon dioxide administered was 70%, and each period of anaesthesia lasted for 3 min. Anaesthesia administered twice a week until the 3rd instar increased the number of instars required to reach maturity. However, repeated anaesthesia after the 4th instar scarcely influenced the number of instars. On the other hand, repeated anesthesia prolonged larval duration whenever administered during the early or late instars. It is thus suggested that anaesthesia by carbon dioxide during larval development has two distinct effects: increasing the number of moults and prolonging larval duration. The former is stage specific and effective only during early instars, whereas the latter is effective during any particular instars until the last instar. The body size of resulting adults remained almost the same as for controls even after the repeated carbon-dioxide anaesthesia as many as 14 times. Some further observations concerning correlations between the number of moults, larval duration and adult body size are shown, and differences between the sexes regarding the number of instars and larval duration are also presented. 相似文献
103.
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105.
Bo Zhang Akira Matsunaga David L. Rainwater Shin-ichiro Miura Keita Noda Hiroaki Nishikawa Yoshinari Uehara Kazuyuki Shirai Masahiro Ogawa Keijiro Saku 《Journal of lipid research》2009,50(9):1832-1841
Electronegative LDL, a charge-modified LDL (cm-LDL) subfraction that is more negatively charged than normal LDL, has been shown to be inflammatory. We previously showed that pravastatin and simvastatin reduced the electronegative LDL subfraction, fast-migrating LDL (fLDL), as analyzed by capillary isotachophoresis (cITP). The present study examined the effects of rosuvastatin on the more electronegative LDL subfraction, very-fast-migrating LDL (vfLDL), and small, dense charge-modified LDL (sd-cm-LDL) subfractions. Patients with hypercholesterolemia or those who were being treated with statins (n = 81) were treated with or switched to 2.5 mg/d rosuvastatin for 3 months. Rosuvastatin treatment effectively reduced cITP cm-LDL subfractions of LDL (vfLDL and fLDL) or sdLDL (sd-vfLDL and sd-fLDL), which were closely related to each other but were different from the normal subfraction of LDL [slow-migrating LDL (sLDL)] or sdLDL (sd-sLDL) in their relation to the levels of remnant-like particle cholesterol (RLP-C), apolipoprotein (apo) C-II, and apoE. The percent changes in cm-LDL or sd-cm-LDL caused by rosuvastatin were correlated with those in the particle concentrations of LDL or sdLDL measured as LDL-apoB or sdLDL-apoB and the levels of HDL-C, RLP-C, apoC-II, and apoE. In conclusion, rosuvastatin effectively reduced both the vfLDL subfraction and sd-cm-LDL subfractions as analyzed by cITP. 相似文献
106.
Both the restoration and deterioration of ultrastructures wereobserved during therewarming of cultured cells of Cornus stoloniferain which chilling at 0?C had caused an apparent change in themorphology of the organelles. Complete restoration of the ultrastructures,moderately altered by the 12-hr chilling, took place within12 hr of wanning at 26?C. Even in cells chilled for 24 hr, severelyaltered ultrastructures were partially or completely repairedin more than fifty percent of the treated cells. Some cellschilled for 24 hr, however, displayed further deteriorationof their ultrastructures during rewarming. Restoration of therough endoplasmic reticulum and the development of polysomesin recovering cells were characteristic of the early stage ofrewarming. Rupture of the tonoplast was sometimes observed duringrewarming of cells chilled for 24 hr. A possible role for therough endoplasmic reticulum and for the integrity of the tonoplastin cell recovery during the chill-warm sequence is discussed.
1Contribution No. 2026 from the Institute of Low TemperatureScience, Hokkaido University.
2This work was supported in part by Grant 248004 from the Ministryof Education. (Received November 6, 1978; ) 相似文献
107.
Takimoto Yuki Monkawa Akira Nagata Kohki Kobayashi Masahiro Kinoshita Mariko Gessei Tomoko Mori Toshiya Kagi Hiroyuki 《Plasmonics (Norwell, Mass.)》2020,15(3):805-811
Plasmonics - Detection and monitoring of SO2 is important because it is a representative toxic gas in the atmospheric environment that is emitted from industrial and natural processes. Localized... 相似文献
108.
Kazumasa Yamada Shinya Sato Masashi Yamazaki Shinya Yoshikawa Akira Kuwata Mutsuo Ichinomiya 《Phycological Research》2020,68(2):178-182
The small phytoplankton genus Triparma belongs to the class Bolidophyceae and contains two distinct forms: silicified species and naked flagellated species (formerly Bolidomonas). Recent studies showed that four silicified species/strains (Triparma laevis f. inornata, T. laevis f. longispina, T. strigata, and T. aff. verrucosa) belong to a single clade that is paraphyletic, because it also contains an unclassified flagellated strain, and is sister to a flagellated species, T. eleuthera. In this study, we isolated and characterized two new strains of silicified species to test the phylogenetic unity of silicified bolidophytes. The isolates were identified as T. retinervis strains because they possessed fine areolation on the cell wall. 18S rDNA and rbcL phylogenetic analyses demonstrated that T. retinervis formed a new silicified clade that is sister to the flagellated species T. pacifica. This reveals that there are at least two distinct clades including both silicified and flagellated Triparma species. 相似文献
109.
Kim Ji Yoon Hirano Yuna Kato Hiroki Noda Akira Im Ran-Young Nishihiro Jun 《Wetlands Ecology and Management》2020,28(2):217-228
Wetlands Ecology and Management - Small valley topology on terraced uplands is a unique groundwater-dependent ecosystem in East Asia. Traditionally, this characteristic valley topology has been... 相似文献
110.
J. Benjamin Miller Amitesh Pratap Akira Miyahara Liang Zhou Stephen Bornemann Richard J. Morris Giles E.D. Oldroyd 《The Plant cell》2013,25(12):5053-5066
The establishment of symbiotic associations in plants requires calcium oscillations that must be decoded to invoke downstream developmental programs. In animal systems, comparable calcium oscillations are decoded by calmodulin (CaM)–dependent protein kinases, but symbiotic signaling involves a calcium/CaM–dependent protein kinase (CCaMK) that is unique to plants. CCaMK differs from the animal CaM kinases by its dual ability to bind free calcium, via calcium binding EF-hand domains on the protein, or to bind calcium complexed with CaM, via a CaM binding domain. In this study, we dissect this dual regulation of CCaMK by calcium. We find that calcium binding to the EF-hand domains promotes autophosphorylation, which negatively regulates CCaMK by stabilizing the inactive state of the protein. By contrast, calcium-dependent CaM binding overrides the effects of autophosphorylation and activates the protein. The differential calcium binding affinities of the EF-hand domains compared with those of CaM suggest that CCaMK is maintained in the inactive state at basal calcium concentrations and is activated via CaM binding during calcium oscillations. This work provides a model for decoding calcium oscillations that uses differential calcium binding affinities to create a robust molecular switch that is responsive to calcium concentrations associated with both the basal state and with oscillations. 相似文献